U.S. patent application number 16/288020 was filed with the patent office on 2020-08-27 for firearm and scope alignment.
The applicant listed for this patent is 90.degree. True North LLC. Invention is credited to D'Arcy Echols.
Application Number | 20200271418 16/288020 |
Document ID | / |
Family ID | 1000003956066 |
Filed Date | 2020-08-27 |
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United States Patent
Application |
20200271418 |
Kind Code |
A1 |
Echols; D'Arcy |
August 27, 2020 |
FIREARM AND SCOPE ALIGNMENT
Abstract
Systems for leveling a firearm receiver and aligning a scope to
the receiver are precisely fabricated and assembled to maximize
accuracy, including high sensitivity spirit levels. A bar assembly
with a high sensitivity spirit level is received in the receiver
with the bar in direct contact with the receiver rails. The bar may
directly contact the full length of the receiver rails. A plate
assembly includes a lower plate for connection to a bench rest, an
upper plate for connection to the receiver, and a mechanism to
pivot the upper plate relative to the lower plate about a pivot
axis for windage adjustment. Methods of use are disclosed.
Inventors: |
Echols; D'Arcy; (Millville,
UT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
90.degree. True North LLC |
Providence |
UT |
US |
|
|
Family ID: |
1000003956066 |
Appl. No.: |
16/288020 |
Filed: |
February 27, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F41G 11/001 20130101;
F41G 1/545 20130101 |
International
Class: |
F41G 1/54 20060101
F41G001/54; F41G 11/00 20060101 F41G011/00 |
Claims
1. A system for leveling a firearm receiver, wherein the receiver
comprises a central longitudinal axis, a cavity, an ejection
window, and a magazine window, wherein the cavity extends
longitudinally into a back end of the receiver and comprises a
first planar datum surface that is parallel to the central
longitudinal axis, wherein the ejection window extends into the
cavity through an upper portion of the receiver between an ejection
window front wall and an ejection window back wall, wherein the
magazine window extends into the cavity through a bottom side of
the receiver between a magazine window front wall and a magazine
window back wall, the system comprising: a bar assembly comprising
a bar and a first level, wherein the bar assembly is removably
connectable to the receiver; wherein the bar extends between a
front end and an opposite back end, wherein the bar comprises a
second planar datum surface that extends between the front and back
ends; wherein the first level is fixed to the bar and is level with
respect to the second planar datum surface; wherein when the bar
assembly is connected to the receiver, the first and second planar
datum surfaces are in direct contact, the bar front end is in front
of the ejection window front wall or the magazine window front
wall, and the bar back end is behind the ejection window back wall
or the magazine window back wall.
2. The system of claim 1, wherein the first planar datum surface
extends between a first front edge and an opposite first back edge;
wherein the second planar datum surface extends between a second
front edge and an opposite second back edge; wherein, when the bar
assembly is connected to the receiver, the second front edge is in
front of the first front edge, and the second back edge is behind
the first back edge.
3. The system of claim 1, wherein when the bar assembly is
connected to the receiver, the second planar datum surface is in
direct contact with at least 40% of the first planar datum
surface.
4. The system of claim 1, wherein the first level is a bullseye
spirit level, wherein the first level is omnidirectionally level
with respect to the second planar datum surface.
5. The system of claim 4, wherein the bar assembly comprises a
second level that is fixed to the bar and is level with respect to
the second planar datum surface, wherein the second level is a tube
spirit level; wherein when the bar assembly is connected to the
receiver, the second level is elongated along a direction that is
perpendicular to the receiver central longitudinal axis.
6. The system of claim 1, further comprising: a plate assembly
comprising a lower plate, an upper plate, and a windage fine
adjustment mechanism; wherein the lower plate is removably
connectable to a main column of a firearm bench rest; wherein the
upper plate is removably connectable to the receiver; wherein the
windage fine adjustment mechanism is actuatable to pivot the upper
plate right or left relative to the lower plate about a pivot
axis.
7. The system of claim 6, wherein when the receiver is connected to
the upper plate, the receiver central longitudinal axis intersects
the pivot axis.
8. A system for leveling a firearm receiver, wherein the receiver
comprises a central longitudinal axis and a cavity, wherein the
cavity extends longitudinally into a back end of the receiver and
comprises a first planar datum surface that is parallel to the
central longitudinal axis, wherein the first planar datum surface
extends between a first front edge and an opposite first back edge,
wherein a first distance extends parallel to the central
longitudinal axis between the first front and back edges, the
system comprising: a bar assembly comprising a bar and a first
level, wherein the bar assembly is removably connectable to the
receiver; wherein the bar comprises a second planar datum surface
that extends between a second front edge and an opposite second
back edge; wherein the first level is fixed to the bar and is level
with respect to the bar second planar datum surface; wherein when
the bar assembly is connected to the receiver, the first and second
planar datum surfaces are in direct contact, a second distance
extends parallel to the central longitudinal axis between the
second front and back edges, wherein the second distance is at
least 50% of the first distance.
9. The system of claim 8, wherein when the bar assembly is
connected to the receiver, the second front edge is in front of the
first front edge, and the second back edge is behind the first back
edge.
10. The system of claim 8, wherein when the bar assembly is
connected to the receiver, the second planar datum surface is in
direct contact with at least 40% of the first planar datum
surface.
11. The system of claim 8, wherein the first level is a bullseye
spirit level, wherein the first level is omnidirectionally level
with respect to the second planar datum surface.
12. The system of claim 11, wherein the bar assembly comprises a
second level that is fixed to the bar and is level with respect to
the second planar datum surface, wherein the second level is a tube
spirit level; wherein when the bar assembly is connected to the
receiver, the second level is elongated along a direction that is
perpendicular to the receiver central longitudinal axis.
13. The system of claim 8, further comprising: a plate assembly
comprising a lower plate, an upper plate, and a windage fine
adjustment mechanism; wherein the lower plate is removably
connectable to a main column of a firearm bench rest; wherein the
upper plate is removably connectable to the receiver; wherein the
windage fine adjustment mechanism is actuatable to pivot the upper
plate right or left relative to the lower plate about a pivot
axis.
14. The system of claim 13, wherein when the receiver is connected
to the upper plate, the receiver central longitudinal axis
intersects the pivot axis.
15. A method of leveling a firearm receiver, wherein the receiver
comprises a central longitudinal axis, a cavity, an ejection
window, and a magazine window, wherein the cavity extends
longitudinally into a back end of the receiver and comprises a
first planar datum surface that is parallel to the central
longitudinal axis, wherein the ejection window extends into the
cavity through an upper portion of the receiver between an ejection
window front wall and an ejection window back wall, wherein the
magazine window extends into the cavity through a bottom side of
the receiver between a magazine window front wall and a magazine
window back wall, the method comprising the steps of: providing a
bar assembly comprising a bar and a first level, wherein the bar
extends between a front end and an opposite back end, and comprises
a second planar datum surface that extends between the front and
back ends, wherein the first level is fixed to the bar and is level
with respect to the second planar datum surface, wherein the first
level comprises a first bubble; coupling the bar assembly to the
receiver so that the first and second planar datum surfaces are in
direct contact, the bar front end is in front of the ejection
window front wall or the magazine window front wall, and the bar
back end is behind the ejection window back wall or the magazine
window back wall; and adjusting the orientation of the receiver so
that the first bubble is centered in the first level.
16. The method of claim 15, further comprising the steps of:
coupling a scope to the receiver, wherein the scope comprises a
vertical reticle; providing a true vertical datum downrange of the
receiver; and after adjusting the orientation of the receiver so
that the first bubble is centered in the first level, adjusting the
orientation of the scope to align the vertical reticle to the true
vertical datum while maintaining the first bubble centered in the
first level; and fixing the scope to the receiver while maintaining
the first bubble centered in the first level and the vertical
reticle aligned to the true vertical datum.
17. The method of claim 15, wherein the first planar datum surface
extends between a first front edge and an opposite first back edge,
wherein the second planar datum surface extends between a second
front edge and an opposite second back edge, the method further
comprising the steps of: coupling the bar assembly to the receiver
so that the second front edge is in front of the first front edge,
and the second back edge is behind the first back edge.
18. The method of claim 15, further comprising the steps of:
coupling the bar assembly to the receiver so that the second planar
datum surface is in direct contact with at least 40% of the first
planar datum surface.
19. The method of claim 15, further comprising the steps of:
providing a plate assembly comprising a lower plate, an upper
plate, and a windage fine adjustment mechanism, wherein the windage
fine adjustment mechanism is actuatable to pivot the upper plate
right or left relative to the lower plate about a pivot axis;
coupling the lower plate to a main column of a firearm bench rest;
and coupling the upper plate to the receiver; wherein adjusting the
orientation of the receiver so that the first bubble is centered in
the first level comprises adjusting the elevation of the receiver
central longitudinal axis by adjusting the bench rest, and
adjusting the windage of the receiver central longitudinal axis by
adjusting the windage fine adjustment mechanism.
20. The method of claim 19, wherein the first level is a bullseye
spirit level, wherein adjusting the orientation of the receiver so
that the first bubble is centered in the first level comprises
omnidirectionally adjusting the orientation of the receiver, the
method further comprising the steps of: coupling a scope to the
receiver, wherein the scope comprises a vertical reticle; providing
a true vertical datum downrange of the receiver; after adjusting
the orientation of the receiver so that the first bubble is
centered in the first level, adjusting the orientation of the scope
to align the vertical reticle to the true vertical datum while
maintaining the first bubble centered in the first level; and
fixing the scope to the receiver while maintaining the first bubble
centered in the first level and the vertical reticle aligned to the
true vertical datum.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] None.
TECHNICAL FIELD
[0002] The present disclosure relates to apparatus and methods for
aligning a firearm barrel axis and a scope axis precisely in a
common plane that is truly vertical, and aligning the vertical and
horizontal scope reticles to be truly vertical and horizontal.
BACKGROUND
[0003] Precisely vertical and horizontal rifle scope crosshairs, or
reticles, become increasingly important to shot accuracy as the
downrange distance increases. A slight cant, or angle error, in the
crosshairs can cause noticeable error or missed shots at long
distances. A cant of five degrees may cause an error of 3.7 inches
at 300 yards.
[0004] Stated another way, the firearm barrel axis, along which the
projectile travels, must lie in a common vertical plane with the
scope axis, along which the shooter sights the target. However,
when the firearm is properly sighted in, the barrel axis is not
parallel to the scope axis. The barrel axis must be tilted with the
muzzle up (elevation) in order to counteract gravitational drop of
the projectile during its flight time to the target. However, the
scope axis is usually truly horizontal. When the barrel and scope
axes lie in a non-vertical plane, the barrel axis elevation angle
causes the projectile to miss low to the right or left of the
target.
[0005] Numerous devices have been developed with the goal of
aligning a firearm barrel axis and a scope axis precisely in a
common vertical plane and aligning the vertical and horizontal
scope reticles to be truly vertical and horizontal. Many of these
devices incorporate spirit levels. Some examples include the Weaver
Crosshair Leveling Kit, the Straight Shot Segway Reticle Kit and
the Wheeler Pro Reticle Leveling Kit. There are at least two
shortcomings with devices such as these: 1) inadequate means for
mounting the devices to the firearm or scope and 2) low precision
fabrication of the devices, in particular low sensitivity spirit
levels.
[0006] The means for mounting the devices to the firearm or scope
may be inadequate for several reasons. Devices may make contact
with firearm or scope features or surfaces which are not reliably
and precisely oriented with respect to the barrel axis, the scope
axis, and/or the vertical plane for alignment. Devices may be
fabricated with compliant parts, such as a magnetic pad, for
primary contact with the firearm or scope. Devices may have
relatively small contact areas or contact lengths with the firearm
or scope features.
[0007] Devices may be fabricated with conventional industry
tolerances for production parts, or in some instances tolerances
that may be wider than industry standard. In an assembly, the
tolerances may stack up unfavorably, resulting in low
precision.
[0008] There is a need for apparatus and methods which overcome
these drawbacks by incorporating means for mounting the apparatus
to reliable precision machined surfaces of the firearm or scope,
which surfaces have known, consistent orientations relative to the
barrel axis, the scope axis, and/or the vertical plane for
alignment. There is also a need for apparatus and methods with high
precision, for example components fabricated and assembled to gage
makers tolerances, and high sensitivity spirit levels.
SUMMARY
[0009] The various systems and methods of the present technology
have been developed in response to the present state of the art,
and in particular, in response to the problems and needs in the art
that have not yet been fully solved by currently available
firearm/scope alignment and leveling technologies. The systems and
methods of the present technology may provide enhanced means for
mounting the associated apparatus to a firearm or scope and
enhanced precision of parts, assemblies, and methods of use.
[0010] To achieve the foregoing, and in accordance with the
technology as embodied and broadly described herein, in an aspect
of the technology, a system for leveling a firearm receiver,
wherein the receiver includes a central longitudinal axis, a
cavity, an ejection window, and a magazine window, wherein the
cavity extends longitudinally into a back end of the receiver and
includes a first planar datum surface that is parallel to the
central longitudinal axis, wherein the ejection window extends into
the cavity through an upper portion of the receiver between an
ejection window front wall and an ejection window back wall,
wherein the magazine window extends into the cavity through a
bottom side of the receiver between a magazine window front wall
and a magazine window back wall, the system includes: a bar
assembly including a bar and a first level, wherein the bar
assembly is removably connectable to the receiver; wherein the bar
extends between a front end and an opposite back end, wherein the
bar includes a second planar datum surface that extends between the
front and back ends; wherein the first level is fixed to the bar
and is level with respect to the second planar datum surface;
wherein when the bar assembly is connected to the receiver, the
first and second planar datum surfaces are in direct contact, the
bar front end is in front of the ejection window front wall or the
magazine window front wall, and the bar back end is behind the
ejection window back wall or the magazine window back wall.
[0011] Embodiments of this aspect may include one or more of the
following attributes. The first planar datum surface extends
between a first front edge and an opposite first back edge; wherein
the second planar datum surface extends between a second front edge
and an opposite second back edge; wherein, when the bar assembly is
connected to the receiver, the second front edge is in front of the
first front edge, and the second back edge is behind the first back
edge. When the bar assembly is connected to the receiver, the
second planar datum surface is in direct contact with at least 40%
of the first planar datum surface. The first level is a bullseye
spirit level, wherein the first level is omnidirectionally level
with respect to the second planar datum surface. The bar assembly
includes a second level that is fixed to the bar and is level with
respect to the second planar datum surface, wherein the second
level is a tube spirit level; wherein when the bar assembly is
connected to the receiver, the second level is elongated along a
direction that is perpendicular to the receiver central
longitudinal axis. The system further including: a plate assembly
including a lower plate, an upper plate, and a windage fine
adjustment mechanism; wherein the lower plate is removably
connectable to a main column of a firearm bench rest; wherein the
upper plate is removably connectable to the receiver; wherein the
windage fine adjustment mechanism is actuatable to pivot the upper
plate right or left relative to the lower plate about a pivot axis.
When the receiver is connected to the upper plate, the receiver
central longitudinal axis intersects the pivot axis.
[0012] In another aspect of the technology, a system for leveling a
firearm receiver, wherein the receiver includes a central
longitudinal axis and a cavity, wherein the cavity extends
longitudinally into a back end of the receiver and includes a first
planar datum surface that is parallel to the central longitudinal
axis, wherein the first planar datum surface extends between a
first front edge and an opposite first back edge, wherein a first
distance extends parallel to the central longitudinal axis between
the first front and back edges, the system includes: a bar assembly
including a bar and a first level, wherein the bar assembly is
removably connectable to the receiver; wherein the bar includes a
second planar datum surface that extends between a second front
edge and an opposite second back edge; wherein the first level is
fixed to the bar and is level with respect to the bar second planar
datum surface; wherein when the bar assembly is connected to the
receiver, the first and second planar datum surfaces are in direct
contact, a second distance extends parallel to the central
longitudinal axis between the second front and back edges, wherein
the second distance is at least 50% of the first distance.
[0013] Embodiments of this aspect may include one or more of the
following attributes. When the bar assembly is connected to the
receiver, the second front edge is in front of the first front
edge, and the second back edge is behind the first back edge. When
the bar assembly is connected to the receiver, the second planar
datum surface is in direct contact with at least 40% of the first
planar datum surface. The first level is a bullseye spirit level,
wherein the first level is omnidirectionally level with respect to
the second planar datum surface. The bar assembly includes a second
level that is fixed to the bar and is level with respect to the
second planar datum surface, wherein the second level is a tube
spirit level; wherein when the bar assembly is connected to the
receiver, the second level is elongated along a direction that is
perpendicular to the receiver central longitudinal axis. The system
further including: a plate assembly including a lower plate, an
upper plate, and a windage fine adjustment mechanism; wherein the
lower plate is removably connectable to a main column of a firearm
bench rest; wherein the upper plate is removably connectable to the
receiver; wherein the windage fine adjustment mechanism is
actuatable to pivot the upper plate right or left relative to the
lower plate about a pivot axis. When the receiver is connected to
the upper plate, the receiver central longitudinal axis intersects
the pivot axis.
[0014] In yet another aspect of the technology, a method of
leveling a firearm receiver, wherein the receiver includes a
central longitudinal axis, a cavity, an ejection window, and a
magazine window, wherein the cavity extends longitudinally into a
back end of the receiver and includes a first planar datum surface
that is parallel to the central longitudinal axis, wherein the
ejection window extends into the cavity through an upper portion of
the receiver between an ejection window front wall and an ejection
window back wall, wherein the magazine window extends into the
cavity through a bottom side of the receiver between a magazine
window front wall and a magazine window back wall, the method
includes the steps of: providing a bar assembly including a bar and
a first level, wherein the bar extends between a front end and an
opposite back end, and includes a second planar datum surface that
extends between the front and back ends, wherein the first level is
fixed to the bar and is level with respect to the second planar
datum surface, wherein the first level includes a first bubble;
coupling the bar assembly to the receiver so that the first and
second planar datum surfaces are in direct contact, the bar front
end is in front of the ejection window front wall or the magazine
window front wall, and the bar back end is behind the ejection
window back wall or the magazine window back wall; and adjusting
the orientation of the receiver so that the first bubble is
centered in the first level.
[0015] Embodiments of this aspect may include one or more of the
following attributes. The method, further including the steps of:
coupling a scope to the receiver, wherein the scope includes a
vertical reticle; providing a true vertical datum downrange of the
receiver; and after adjusting the orientation of the receiver so
that the first bubble is centered in the first level, adjusting the
orientation of the scope to align the vertical reticle to the true
vertical datum while maintaining the first bubble centered in the
first level; and fixing the scope to the receiver while maintaining
the first bubble centered in the first level and the vertical
reticle aligned to the true vertical datum. The first planar datum
surface extends between a first front edge and an opposite first
back edge, wherein the second planar datum surface extends between
a second front edge and an opposite second back edge, the method
further including the steps of: coupling the bar assembly to the
receiver so that the second front edge is in front of the first
front edge, and the second back edge is behind the first back edge.
The method, further including the steps of: coupling the bar
assembly to the receiver so that the second planar datum surface is
in direct contact with at least 40% of the first planar datum
surface. The method, further including the steps of: providing a
plate assembly including a lower plate, an upper plate, and a
windage fine adjustment mechanism, wherein the windage fine
adjustment mechanism is actuatable to pivot the upper plate right
or left relative to the lower plate about a pivot axis; coupling
the lower plate to a main column of a firearm bench rest; and
coupling the upper plate to the receiver; wherein adjusting the
orientation of the receiver so that the first bubble is centered in
the first level includes adjusting the elevation of the receiver
central longitudinal axis by adjusting the bench rest, and
adjusting the windage of the receiver central longitudinal axis by
adjusting the windage fine adjustment mechanism. The first level is
a bullseye spirit level, wherein adjusting the orientation of the
receiver so that the first bubble is centered in the first level
includes omnidirectionally adjusting the orientation of the
receiver, the method further including the steps of: coupling a
scope to the receiver, wherein the scope includes a vertical
reticle; providing a true vertical datum downrange of the receiver;
and after adjusting the orientation of the receiver so that the
first bubble is centered in the first level, adjusting the
orientation of the scope to align the vertical reticle to the true
vertical datum while maintaining the first bubble centered in the
first level; and fixing the scope to the receiver while maintaining
the first bubble centered in the first level and the vertical
reticle aligned to the true vertical datum.
[0016] These and other features and advantages of the present
technology will become more fully apparent from the following
description and appended claims, or may be learned by the practice
of the technology as set forth hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Exemplary embodiments of the technology will become more
fully apparent from the following description and appended claims,
taken in conjunction with the accompanying drawings. Understanding
that these drawings depict only exemplary embodiments and are,
therefore, not to be considered limiting of the scope of the
technology, the exemplary embodiments will be described with
additional specificity and detail through use of the accompanying
drawings in which:
[0018] FIG. 1 is a perspective view of a first assembly, referred
to as a reticle bar;
[0019] FIG. 2 is another perspective view of the first assembly of
FIG. 1 from a different direction;
[0020] FIG. 3 is a top view of the first assembly of FIG. 1;
[0021] FIG. 4 is a bottom view of the first assembly of FIG. 1;
[0022] FIG. 5 is a front view of the first assembly of FIG. 1;
[0023] FIG. 6 is a back view of the first assembly of FIG. 1;
[0024] FIG. 7 is a left view of the first assembly of FIG. 1;
[0025] FIG. 8 is a right view of the first assembly of FIG. 1;
[0026] FIG. 9 is an exploded perspective view of the first assembly
of FIG. 1;
[0027] FIG. 10 is another exploded perspective view of the first
assembly of FIG. 1 from a different direction;
[0028] FIG. 11 is a perspective view of a receiver;
[0029] FIG. 12 is another perspective view of the receiver of FIG.
11 from a different direction;
[0030] FIG. 13 is another perspective view of the receiver of FIG.
11 from a different direction;
[0031] FIG. 14 is another perspective view of the receiver of FIG.
11 from a different direction;
[0032] FIG. 15 is another perspective view of the receiver of FIG.
11 from a different direction;
[0033] FIG. 16 is another perspective view of the receiver of FIG.
11 from a different direction;
[0034] FIG. 17 is a cross-sectional view of a top half of the
receiver of FIG. 11, taken along section line 17-17 of FIG. 18;
[0035] FIG. 18 is a right view of the receiver of FIG. 11;
[0036] FIG. 19 is a cross-sectional view of a bottom half of the
receiver of FIG. 11, taken along section line 19-19 of FIG. 18;
[0037] FIG. 20 is a perspective view of the first assembly of FIG.
1 operatively assembled in the receiver of FIG. 11;
[0038] FIG. 21 is a perspective view of the first assembly and
receiver of FIG. 20 from a different direction;
[0039] FIG. 22 is a front view of the first assembly and receiver
of FIG. 20;
[0040] FIG. 23 is a right view of the first assembly and receiver
of FIG. 20;
[0041] FIG. 24 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 24-24 of FIG. 22;
[0042] FIG. 25 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 25-25 of FIG. 23;
[0043] FIG. 26 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 26-26 of FIG. 23;
[0044] FIG. 27 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 27-27 of FIG. 23;
[0045] FIG. 28 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 28-28 of FIG. 23;
[0046] FIG. 29 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 29-29 of FIG. 23;
[0047] FIG. 30 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 30-30 of FIG. 23;
[0048] FIG. 31 is a cross-sectional view of the first assembly and
receiver of FIG. 20, taken along section line 31-31 of FIG. 23;
[0049] FIG. 32 is a right detail view of a portion of the first
assembly of FIG. 1 operatively arranged adjacent to a bolt
stop/release;
[0050] FIG. 33 is a bottom detail view of a portion of the first
assembly and bolt stop/release of FIG. 32;
[0051] FIG. 34 is a right detail view of a portion of the first
assembly of FIG. 1 operatively arranged adjacent to another bolt
stop/release;
[0052] FIG. 35 is a bottom detail view of a portion of the first
assembly and bolt stop/release of FIG. 34;
[0053] FIG. 36 is a perspective view of a plate sub-assembly of a
second assembly operatively assembled to a rifle bench rest, an
adapter block base of the second assembly operatively assembled to
the plate sub-assembly, three adapter blocks of the second
assembly, and two more main columns for interchangeable use in the
rifle bench rest, the second assembly also referred to as a
sighting holder;
[0054] FIG. 37 is an exploded perspective view of the plate
sub-assembly and adapter block base of FIG. 36;
[0055] FIG. 38 is a top view of the plate sub-assembly and adapter
block base of FIG. 36;
[0056] FIG. 39 is a front view of the plate sub-assembly and
adapter block base of FIG. 38, with one of the adapter blocks of
FIG. 36 operatively assembled to the adapter block base;
[0057] FIG. 40 is a cross-sectional view of the plate sub-assembly,
adapter block base, and adapter block of FIG. 39, taken along
section line 40-40 of FIG. 39;
[0058] FIG. 41 is a perspective view of the plate sub-assembly,
rifle bench rest, and adapter block base of FIG. 36, with another
one of the adapter blocks of FIG. 36 operatively assembled to the
adapter block base;
[0059] FIG. 42 is a perspective view of the plate sub-assembly,
rifle bench rest, adapter block base, and adapter block of FIG. 41
operatively assembled to the first assembly and receiver of FIG.
20;
[0060] FIG. 43 is a top view of the plate sub-assembly, rifle bench
rest, adapter block base, adapter block, first assembly, and
receiver of FIG. 42;
[0061] FIG. 44 is another perspective view of the plate
sub-assembly, rifle bench rest, adapter block base, adapter block,
first assembly, and receiver of FIG. 42 from a different
direction;
[0062] FIG. 45 is a back view of the plate sub-assembly, rifle
bench rest, adapter block base, adapter block, first assembly, and
receiver of FIG. 42 operatively assembled to a rifle scope, shown
schematically;
[0063] FIG. 46 is a perspective view of the plate sub-assembly,
adapter block base, and adapter block of FIG. 38 operatively
assembled to the rifle bench rest of FIG. 36;
[0064] FIG. 47 is a back view of the plate sub-assembly, adapter
block base, adapter block, and rifle bench rest of FIG. 46;
[0065] FIG. 48 is a top view of the plate sub-assembly, adapter
block base, adapter block, and rifle bench rest of FIG. 46;
[0066] FIG. 49 is a perspective view of the plate sub-assembly,
rifle bench rest, and adapter block base of FIG. 36, with yet
another one of the adapter blocks of FIG. 36 operatively assembled
to the adapter block base;
[0067] FIG. 50 is a perspective view of the plate sub-assembly,
rifle bench rest, adapter block base, and adapter block of FIG. 49,
with a rifle scope operatively assembled to the adapter block;
[0068] FIG. 51 is a back view of the plate sub-assembly, rifle
bench rest, adapter block base, adapter block, and rifle scope of
FIG. 50;
[0069] FIG. 52 is a side view of the plate sub-assembly, rifle
bench rest, adapter block base, adapter block, and rifle scope of
FIG. 50;
[0070] FIG. 53 is a bottom view of an AR action;
[0071] FIG. 54 is an oblique view of the AR action of FIG. 53
coupled to a scope, the AR action being coupled to a third
assembly, referred to as an AR sighting holder, the third assembly
coupled to a rifle bench rest;
[0072] FIG. 55 is an oblique detail view of a portion of the AR
action and third assembly of FIG. 54;
[0073] FIG. 56 is an oblique detail view of a portion of the AR
action, third assembly, and rifle bench rest of FIG. 54;
[0074] FIG. 57 is an oblique view of the AR action, scope, third
assembly, and rifle bench rest of FIG. 54, the AR action fully
coupled to the third assembly;
[0075] FIG. 58 is an oblique detail view of a portion of the third
assembly and rifle bench rest of FIG. 54;
[0076] FIG. 59 is an oblique detail view of a portion of the AR
action, third assembly, and rifle bench rest of FIG. 54;
[0077] FIG. 60 is another oblique view of the AR action, scope,
third assembly, and rifle bench rest of FIG. 54; and
[0078] FIG. 61 is yet another oblique view of the AR action, scope,
third assembly, and rifle bench rest of FIG. 54.
DETAILED DESCRIPTION
[0079] Exemplary embodiments of the technology will be best
understood by reference to the drawings, wherein like parts are
designated by like numerals throughout. It will be readily
understood that the components of the technology, as generally
described and illustrated in the figures herein, could be arranged
and designed in a wide variety of different configurations. Thus,
the following more detailed description of the embodiments of the
apparatus, system, and method is not intended to limit the scope of
the invention, as claimed, but is merely representative of
exemplary embodiments of the technology.
[0080] The phrases "connected to," "coupled to" and "in
communication with" refer to any form of interaction between two or
more entities, including mechanical, electrical, magnetic,
electromagnetic, fluid, and thermal interaction. Two components may
be functionally coupled to each other even though they are not in
direct contact with each other. The term "abutting" refers to items
that are in direct physical contact with each other, although the
items may not necessarily be attached together. The phrase "fluid
communication" refers to two features that are connected such that
a fluid within one feature is able to pass into the other
feature.
[0081] The word "exemplary" is used herein to mean "serving as an
example, instance, or illustration." Any embodiment described
herein as "exemplary" is not necessarily to be construed as
preferred or advantageous over other embodiments. While the various
aspects of the embodiments are presented in drawings, the drawings
are not necessarily drawn to scale unless specifically
indicated.
[0082] Standard firearm planes of reference, directional terms, and
descriptive terminology are employed in this specification with
their ordinary and customary meanings. "Front" or "muzzle," "rear"
or "back" or "breech," "left," "right," "top" or "up," and "bottom"
or "down" are defined from the point of view of a shooter in a
conventional shooting position relative to an apparatus or a part.
"Downrange" means in front of the apparatus at a distance
representative of a planned distance to target. A firearm has a
barrel axis, or shooting axis, which is the central longitudinal
axis of the barrel, along which a bullet travels as it is fired
from the firearm. A scope has a scope axis, or sighting axis, which
is the central longitudinal axis of the scope, along which a
shooter sights on a target. When the firearm and scope are properly
aligned, the barrel axis and the scope axis lie in a common
vertical plane. Typically, the scope axis is above the barrel
axis.
[0083] "Gage makers tolerance," abbreviated as "GMT," is defined in
this specification as a tolerance much smaller than conventional
industry tolerances for production parts. GMTs are conventionally
used in fabrication of the gages used to inspect production parts.
ASME B89 is one example of a standard for dimensional metrology
which sets forth specification of dimensional measuring instruments
and gages for measuring various geometrical characteristics such as
lengths, plane surfaces, angles, circles, cylinders, cones,
spheres, and tori.
[0084] Referring to FIGS. 1-10, a first assembly 100 may include a
base 102, a bullseye level 104, a tube level 106, a roller 108, a
screw 114, and a set screw 120. Three rollers 108, 110, 112; three
screws 114, 116, 118; and two set screws 120, 122 are shown. The
first assembly 100 may be referred to as a reticle bar, reticle
assembly, or bar assembly.
[0085] The base 102 may be a long, thin, substantially rectangular
bar that is elongated between a front end 130 and a back end 132.
The base 102 has a top side 134, a bottom side 136, a right side
138, and a left side 140. First, second, and third holes 142, 144,
146 may extend through the base 102 between the top and bottom
sides 134, 136. The holes 142, 144, 146 may be centered in the
right-left width of the base 102. The first hole 142 may be near
the front end 130. The second and third holes 144, 146 may be close
together, about halfway between the front and back ends 130, 132,
with the second hole closer to the front end and the third hole
closer to the back end. The holes 142, 144, 146 may be internally
threaded. A triangular group of three holes 148, 150, 152 may
extend through the base 102 between the top and bottom sides 134,
136. The holes 148, 150, 152 may be close together near the back
end 132, with the hole 148 centered in the right-left width of the
base 102 and closer to the front end 130 and the holes 150, 152
side by side closer to the back end. The hole 150 may be closer to
the left side 140 and the hole 152 may be closer to the right side
138. A pair of holes 154, 156 may extend through the base 102
between the top and bottom sides 134, 136. The holes 154, 156 may
be closer to the back end than the holes 150, 152. The hole 154 may
be closer to the left side 140 and the hole 156 may be closer to
the right side 138. A transverse groove 158 may extend into the
base 102 from the top side 134 and across the base between the
right and left sides 138, 140. The groove 158 may have a circular
cross-sectional shape when viewed in a right or left view. The
center of the circular cross-sectional shape may be recessed below
the top side 134 so that the groove 158 is undercut (FIGS. 7, 8,
24). A longitudinal notch 160 may extend into the base 102 along
the edge between the bottom and right sides 136, 138. The front end
of the notch 160 may be close to the front side of the hole 144.
The back end of the notch 160 may be between the hole 146 and the
hole 148. The notch 160 may have a rectangular cross-sectional
shape when viewed in a front or back view. Another longitudinal
notch 162 may extend into the base 102 along the edge between the
bottom and left sides 136, 140. The notch 162 may be a mirror image
of the notch 160.
[0086] The bullseye level 104 may be a cylindrical part with a top
end 164 and a bottom end 166. The bullseye level 104 may be
referred to as a circular spirit level or an omnidirectional spirit
level. An enlarged flange 168 may extend around the bottom end. A
triangular group of three holes 170, 172, 174 may extend through
the flange 168 between the top and bottom ends 164, 166. The
bullseye level 104 includes a fluid reservoir 176 with a clear wall
across the top end. The fluid reservoir includes a bubble of air or
other gas that is movable within the fluid. The clear top wall may
include indicia, such as concentric circular marks, to aid the user
in centering the bubble and thus leveling the bullseye level 104.
The clear top wall is preferably made of glass. Geier & Bluhm
of New York manufactures a bullseye level that the inventor finds
suitable.
[0087] The tube level 106 may be an elongated clear part that
extends between a right end 180 and a left end 182. While the tube
level 106 may appear to be a cylindrical part, it may actually have
an oval shape, a barrel shape, or another curved shape of its side
wall in a front or back view. The curvature may be subtle, in other
words, it may have a large radius of curvature. The tube level 106
is a fluid reservoir with a bubble of air or other gas that is
movable within the fluid. The tube level 106 may include indicia,
such as transverse lines, to aid the user in centering the bubble
and thus leveling the tube level. The tube level 106 is preferably
made of glass. W. A. Moyer of Kansas manufactures a tube level that
the inventor finds suitable.
[0088] The "sensitivity" of a spirit level refers to how easily the
bubble moves within the fluid reservoir when the spirit level is
tilted. Greater sensitivity equates to a more precise spirit level.
Sensitivity may be measured in millimeters per meter (mm/m) or
arcminute (arcmin). The standard for most spirit levels on the
market is a sensitivity of 10 mm/m. Preferably, the bullseye level
104 and the tube level 106 are high precision parts with
sensitivities less than 10 mm/m, for example 5 mm/m, 2 mm/m, or 1
mm/m.
[0089] The roller 108 may be a ball nose spring plunger or other
compliant component. The roller 108 may be externally threaded. The
rollers 110, 112 may be identical to the roller 108.
[0090] The screw 114 may be a socket head cap screw. The screws
116, 118 may be identical to the screw 114.
[0091] The set screw 120 may be a cup point socket set screw. The
set screw 122 may be identical to the set screw 120.
[0092] The first assembly 100 may be operatively assembled by
inserting the roller 108 into the hole 142 of the base 102 with the
ball nose protruding from the top side 134; inserting the roller
110 into the hole 144 with the ball nose protruding from the top
side 134; inserting the roller 112 into the hole 146 with the ball
nose protruding from the top side 134; coupling the bullseye level
104 to the base 102 by inserting the screw 114 through the hole 170
and into the hole 148, inserting the screw 116 through the hole 172
and into the hole 150, and inserting the screw 118 through the hole
174 and into the hole 152; and coupling the tube level 106 to the
base 102 by sliding the tube level into the groove 158 from the
right or left side 138, 140, inserting the set screw 120 into the
hole 154 to press against the bottom side of the tube level, and
inserting the set screw 122 into the hole 156 to press against the
bottom side of the tube level. Inserting the rollers 108, 110, 112
into the corresponding holes 142, 144, 146 may involve threading
the rollers into the holes or press-fitting the rollers into the
holes. Coupling the bullseye level 104 and/or the tube level 106 to
the base 102 may include precisely leveling the bullseye level
and/or the tube level to the bottom side 136 of the base 102, for
example by adjusting the screws 114, 116, 118 and/or set screws
120, 122 to center the bubble(s) to GMT while the bottom side 136
rests upon a precision datum surface such as a calibrated granite
surface plate. A surface plate is a solid, flat plate commonly used
as the main horizontal reference plane for precision inspection,
layout, and tooling setup.
[0093] When the first assembly 100 is operatively assembled, the
bullseye level 104 and the tube level 106 may be precisely leveled
with respect to the bottom side 136 of the base 102. The tops of
the rollers 108, 110, 112 may be precisely positioned at a specific
distance from the bottom side 136. Thus, the bottom side 136 may
function as a primary planar datum surface of the first assembly
100.
[0094] Referring to FIGS. 11-19, a receiver 200 is shown. The
illustrated receiver 200 is a flat bottomed Mod-70 which includes
certain features that are common to many receivers. Only those
features which interact with components of the current technology
will be described herein.
[0095] The receiver 200 extends between a front end 210 and a back
end 212. A central longitudinal axis 214 extends between the front
and back ends 210, 212. When the receiver 200 is operatively
assembled into a firearm, the axis 214 extends along the center of
the barrel. Thus the axis 214 is the barrel axis or shooting axis
of the receiver 200. The exterior of the receiver 200 includes a
flat bottom surface 216 with an internally threaded hole 218 that
extends up through the bottom surface 216 into the receiver 200
near the front end 210. The hole 218 may be referred to as a front
guard screw hole. The interior of the receiver 200 includes a
longitudinal cavity 220. The cavity includes a front right lower
planar surface 222, a rear right lower planar surface 224, and a
left lower planar surface 226. In the example shown, the front
right lower planar surface 222 has an area of 1007 mm.sup.2 and a
135 mm length measured parallel to the axis 214, the rear right
lower planar surface 224 has an area of 142 mm.sup.2 and a 22 mm
length parallel to the axis 214, and the left lower planar surface
226 has an area of 808 mm.sup.2 and a 167 mm length parallel to the
axis 214. The lower planar surfaces 222, 224, 226 may be coplanar,
and may be referred to as lower rails. The lower planar surfaces
222, 224, 226 may be parallel to the axis 214. The lower planar
surfaces 222, 224, 226 are reliable precision machined surfaces
which are excellent primary datum features for the disclosed
technology. Taken together, the lower planar surfaces 222, 224, 226
may be treated as a single lower planar datum surface 221. In the
example shown, the lower planar datum surface 221 has an area of
1957 mm.sup.2 and a 169 mm overall length measured parallel to the
axis 214. The cavity 220 includes a front right upper planar
surface 228, a rear right upper planar surface 230, and a left
upper planar surface 232. The upper planar surfaces 228, 230, 232
may be coplanar, and may be referred to as upper rails. The upper
planar surfaces 228, 230, 232 are reliable precision machined
surfaces which are excellent primary datum features for the
disclosed technology. Taken together, the upper planar surfaces
228, 230, 232 may be treated as a single upper planar datum surface
227. The upper planar surfaces 228, 230, 232 may be parallel to the
lower planar surfaces 222, 224, 226. Taken together, the lower and
upper rails may be referred to as a bolt raceway. The cavity 220
includes a first cylindrical portion 234 which extends rearwardly
into the front end 210 and a second cylindrical portion 236 which
extends rearwardly from the first cylindrical portion 234 and
concentric with the first cylindrical portion. The first
cylindrical portion 234 receives a barrel (indicated in dashed
lines in FIG. 43). The diameter of the second cylindrical portion
236 may be greater than the diameter of the first cylindrical
portion 234, so that a rear-facing annular wall 238 is formed
between the first and second cylindrical portions 234, 236. The
wall 238 may be referred to as a chamber breech. The right side of
the second cylindrical portion 236 may extend rearwardly past the
wall 238 to intersect the front right lower planar surface 222 and
the front right upper planar surface 228 to form outer edges of the
planar surfaces. An upper concave surface 240 extends rearwardly
from the second cylindrical portion 236. The upper concave surface
240 may be a section of a cylinder, and may be concentric with the
first and second cylindrical portions 234, 236. The diameter of the
upper concave surface 240 may be less than the diameter of the
second cylindrical portion 236, so that a front-facing wall 242 is
formed between the second cylindrical portion and the upper concave
surface. The upper concave surface 240 may intersect the upper
planar surfaces 228, 230, 232 to form inner edges of the upper
planar surfaces. A front lower concave surface 244 extends
rearwardly from the second cylindrical portion 236. The front lower
concave surface 244 may be a section of the same cylinder as the
upper concave surface 240. Thus, the wall 242 may exist between the
second cylindrical portion 236 and the front lower concave surface
244. The wall 242 may be the front boundary of the front right
upper planar surface 228 and the left lower planar surface 226. The
front lower concave surface 244 may intersect the lower planar
surfaces 222, 226 to form inner edges of the lower planar surfaces.
A longitudinal window 246 extends upwardly into the receiver 200 to
intersect the cavity 220 to the rear of the front lower concave
surface 244. The window 246 may be referred to as a magazine window
or a feed window. A rear lower concave surface 248 extends
rearwardly from the window 246. The rear lower concave surface 248
may be a section of the same cylinder as the upper concave surface
240. The rear lower concave surface 248 may intersect the lower
planar surfaces 222, 224, 226 to form inner edges of the lower
planar surfaces. A longitudinal window 250 extends into the top and
right sides of the receiver 200 to intersect the cavity 220. The
window 250 may be referred to as an ejection window or ejection
port. Referring to FIGS. 17-19, the front end or wall of the window
250 may be slightly in front of the front end or wall of the window
246. The top portion between the front end 210 and the window 250
may be referred to as a front bridge or front arch. The rear end or
wall of the window 250 may be slightly in front of the rear end or
wall of the window 246. The top portion behind the window 250 may
be referred to as a rear bridge or rear arch. A rear right concave
surface 252 extends rearwardly from the rear end of the window 250.
The rear right concave surface 252 intersects the rear right lower
planar surface 224 and the rear right upper planar surface 230 to
form outer edges of the planar surfaces. The rear right concave
surface 252 may be a section of the same cylinder as the second
cylindrical portion 236. A front left concave surface 254 extends
rearwardly from the wall 242 past the rear end of the window 246,
intersects the left upper planar surface 232 and the left lower
planar surface 226 to form outer edges of the planar surfaces, and
may be a section of the same cylinder as the first cylindrical
portion 234. A window 256 extends into the left side of the
receiver 200 to intersect the cavity 220 and form the rear end of
the front left concave surface 254. A rear left concave surface 258
extends rearwardly from the window 256, intersects the left upper
planar surface 232 and the left lower planar surface 226 to form
outer edges of the planar surfaces, and may be a section of the
same cylinder as the first cylindrical portion 234.
[0096] Referring to FIGS. 20-31, the first assembly 100 may be
operatively assembled to the receiver 200 by inserting the front
end 130 of the base 102 of the first assembly 100 into the back end
of the cavity 220 of the receiver 200 and advancing the first
assembly 100 within the cavity 220 so that the bottom side 136
directly contacts at least one, and preferably all, of the lower
planar surfaces 222, 224, 226; the top side 134 faces the upper
planar surfaces 228, 230, 232; the roller 108 contacts the upper
concave surface 240 in front of the window 250; and at least one
roller 110, 112 contacts the upper concave surface 240 to the rear
of the window 246. The front end 130 of the base 102 may contact
the chamber breech, in other words, the wall 238 or the back or
breech end of a barrel coupled to the receiver 200.
[0097] When the first assembly 100 is operatively assembled to the
receiver 200, the bottom side 136 is directly adjacent to the front
ends of the lower planar surfaces 222, 226 and the rear ends of the
lower planar surfaces 222, 224. The front end of the bottom side
136 is in front of the front end of the window 246, may be in front
of the front end of the window 250, and may be in front of the
front ends of the lower planar surfaces 222, 226. The rear end of
the bottom side 136 is behind the rear end of the window 250, may
be behind the rear end of the window 246, and may be behind the
rear ends of the lower planar surfaces 222, 224. The right and left
sides 138, 140 are directly adjacent to the outer edges of the
lower planar surfaces 222, 224, 226. Thus, surface contact between
the bottom side 136 and the lower planar datum surface 221 is
maximized within the constraint of physically sliding the first
assembly 100 into the cavity 220 from the rear. Said another way,
the bottom side 136 contacts substantially the full length of the
lower planar datum surface 221 measured parallel to the axis 214.
From a metrology point of view, there will be at least three points
of contact between the bottom side 136 and the lower planar datum
surface 221. The three points of contact establish a primary datum
plane 260 common to the first assembly 100 and the receiver 200.
The primary datum plane 260 may be referred to as a horizontal
datum plane. While this description is made in the context of a
continuous flat planar bottom side 136, it is contemplated that the
bottom side 136 may instead comprise discontinuous patches, or
points, for contacting the lower planar datum surface 221. Taken
together, the discontinuous patches or points may function as a
primary planar datum surface. Whether the bottom side 136 is
continuous or discontinuous, the bottom side 136 preferably
directly contacts the full length of the lower planar datum surface
221 measured parallel to the axis 214.
[0098] In the example shown, when the first assembly 100 is
operatively assembled to the receiver 200 as shown in FIGS. 20-31,
on an area basis, the bottom side 136 contacts 833 mm.sup.2 (43%)
of the lower planar datum surface 221, including contacting 379
mm.sup.2 (38%) of the front right lower planar surface 222, 26
mm.sup.2 (18%) of the rear right lower planar surface 224, and 428
mm.sup.2 (53%) of the left lower planar surface 226. It is
contemplated that the bottom side 136 may be in direct contact with
at least 40% of the area of the lower planar datum surface 221, the
front right lower planar surface 222, or the left lower planar
surface 226. On a length basis, parallel to the axis 214, the
bottom side 136 contacts the full length of the lower planar datum
surface 221. However, it is contemplated that the bottom side 136
may contact at least 50% of the length of the lower planar datum
surface 221, the front right lower planar surface 222, or the left
lower planar surface 226.
[0099] When the first assembly 100 is operatively assembled to the
receiver 200, the bullseye level 104 and the tube level 106 are
behind the back end of the receiver 200. The tube level 104 is
oriented with its length, from right to left, perpendicular to the
receiver axis 214.
[0100] The roller 108 contacts the upper concave surface 240 in
front of the window 250. At least one roller 110, 112 contacts the
upper concave surface 240 to the rear of the window 246. Two rear
rollers 110, 112 are provided to accommodate different size
receivers 200. Preferably, the rollers 108, 110, 112 touch intact
portions of the upper concave surface 240 away from any holes or
other interruptions of the upper concave surface. Preferably, the
rollers 108, 110, 112 are compliant, for example biased to extend
up from the top side 134 of the base 102. In this arrangement,
compliant rollers 108, 110, 112 may deflect downward as they
contact the upper concave surface 240. The downward deflection may
serve at least two purposes: to automatically accommodate
dimensional variations between the upper concave surface 240 and
the primary datum plane 260 in individual receivers, and to
automatically seek the highest location against the upper concave
surface due to the bias which urges the rollers 108, 110, 112 up
toward their undeflected state. As the rollers 108, 110, 112 seek
the highest location against the upper concave surface 240, the
first assembly 100 may be urged right or left within the cavity 220
as a result, thus automatically aligning the first assembly 100
along the interior crest of the upper concave surface 240. From a
metrology point of view, each roller will have a point of contact
with the upper concave surface 240. Two points of contact establish
a secondary datum line 262 along the interior crest of the upper
concave surface 240, which establishes a secondary datum plane 264
that contains the secondary datum line 262 and is perpendicular to
the primary datum plane 260. The secondary datum plane 264 may be
referred to as a vertical datum plane. In the nominal design of the
receiver 200, the secondary datum plane 264 may also contain the
axis 214. However, it is contemplated that the first assembly 100
may rest asymmetrically within the cavity 220, in other words,
offset to the right or left. This may cause the secondary datum
plane 264 to be left or right of the axis 214. Alternatively, even
if the first assembly 100 rests to the right or left, the rollers
108, 110, 112 may be positioned relative to the base 102 to
counteract this eccentricity, so that the secondary datum plane 264
may contain the axis 214.
[0101] When the first assembly 100 is operatively assembled to the
receiver 200, various parts normally associated with the receiver
200 may remain assembled to the receiver 200 without interfering
with the first assembly 100. For example, the trigger assembly
and/or ejector may remain assembled to the receiver 200 without
pushing on the first assembly 100. Preferably, the magazine well
assembly and stock are disassembled from the receiver 200 before
the first assembly 100 is operatively assembled to the receiver
200.
[0102] Referring to FIGS. 32-33, side and bottom views show the
first assembly 100 operatively arranged adjacent to a bolt
stop/release 202 characteristic of a Winchester Model 70 action.
The bolt stop/release 202 has a front end 266 and a back end 268.
The bolt stop/release 202 may have a thin, flat body 270 that
extends between the front and back ends 266, 268. The bolt
stop/release 202 may have an upright arm 272 which extends up from
the body 270. The arm 272 may jog to the left as it extends up from
the body 270, so that an upper portion 274 of the arm is offset, or
spaced apart, to the left of the body. The front end of the body
270 is received within the left notch 162 of the base 102 of the
first assembly 100 with sufficient clearance so that the bolt
stop/release 202 does not push on the first assembly 100. The upper
portion 274 of the arm 272 extends up beside the left side 140,
outside the notch 162. The left notch 162 may be sized and shaped
to also receive the Winchester Model 70 ejector with clearance, or
another left notch (not shown) may be provided for this
purpose.
[0103] Referring to FIG. 34-35, side and bottom views show the
first assembly 100 operatively arranged adjacent to a bolt
stop/release 204 characteristic of a Remington 700 action. The bolt
stop/release 204 has a front end 276 and a back end 278. The bolt
stop/release 204 may have a thin, flat body 280 that extends
between the front and back ends 276, 278. The bolt stop/release 204
may have an upper protrusion 282 in a rear portion of the body 280.
The front end of the body 280 is received within the left notch 162
of the base 102. The protrusion 282 may also be received within the
notch 162. There is sufficient clearance so that the bolt
stop/release 204 does not push on the first assembly 100. The left
notch 162 may be sized and shaped to also receive the Remington 700
ejector with clearance, or another left notch (not shown) may be
provided for this purpose.
[0104] FIGS. 32-35 show two examples of bolt stop/releases 202, 204
designed for right-handed shooters. The first assembly 100 is also
compatible with bolt stop/releases 202, 204 designed for
left-handed shooters, in which case the bolt stop/releases are
mirrored about a longitudinal vertical plane (such as plane 264)
and received in the right notch 160 of the base 102. Furthermore,
various embodiments of the first assembly 100 may be provided with
notches that are sized, shaped, and located to correspond to
various firearm actions, such as a Borden action or a Defiance
action.
[0105] Referring to FIG. 36, a second assembly 300 may include a
plate sub-assembly 302, an adapter block base sub-assembly 304,
and/or an adapter block 306. Three adapter blocks 306, 308, 310 are
shown for interchangeable connection to the adapter block base 304.
Each adapter block 306, 308, 310 is designed to securely couple to
a particular style or class of receiver. These are but three
examples. Preferably, each adapter block is designed so that the
receiver may be secured to its adapter block using the receiver's
front guard screw. The second assembly 300 may be referred to as a
sighting holder or sighting assembly. The adapter block base
sub-assembly 304 is shown operatively assembled to the plate
sub-assembly 302, which is operatively assembled to a rifle bench
rest 400. Referring briefly to FIG. 45, the plate sub-assembly 302
may be coupled to a main column 402 of the rifle bench rest 400.
FIG. 36 also illustrates two more main columns 404, 406 for
interchangeable assembly in the rifle bench rest 400. The second
assembly 300 has a front end 312, a back end 314, a right side 316,
and a left side 318.
[0106] Referring to FIG. 37, the plate sub-assembly 302 may include
a first plate 320, second plate 322, fasteners 324, 326, 328, 330,
spring plunger 332, and pin 334. The first plate 320 may be
referred to as a lower plate and the second plate 322 may be
referred to as a top plate.
[0107] The first plate 320 has five holes 350, 352, 354, 356, 358.
The holes 350, 352, 354, 356 extend through the first plate 320
along a top-bottom direction. The holes 350, 352, 354 are centrally
located between the right and left sides 316, 318 in a linear
arrangement from front to back. The holes 350, 352 are in the front
half of the first plate 320 and the hole 354 is close to the back
end 314. The holes 350, 352 may have internal threads; or hole 352
may be unthreaded (smooth). The top end of the hole 352 may include
a countersink. FIG. 40 illustrates that the bottom end of the hole
352 may include a counterbore. The hole 354 may be circular, or
elongated along a right-left direction, for example oval. The hole
356 is to the right rear of hole 354. The hole 356 may be elongated
along the right-left direction, or circular. The hole 358 extends
through the first plate 320 along the right-left direction and
intersects the hole 354. The right and/or left portions of hole 358
may have internal threads. The first plate 320 may include an
optional bullseye level or tube level (not shown) for preliminary
leveling.
[0108] The second plate 322 has six holes 360, 362, 364, 366, 368,
370 that extend through the second plate along a top-bottom
direction. The holes 360, 362, 364, 366, 368 are centrally located
between the right and left sides 316, 318 in a linear arrangement
from front to back. The hole 360 is near the front end 312,
corresponding to the location of hole 350 of the first plate 320.
The holes 362, 364, 366 are grouped in a central region of the
second plate 322. The hole 364 may be internally threaded. The hole
368 is near the back end 314, corresponding to the location of hole
354 of the first plate 320. The hole 370 is to the right rear of
hole 368, corresponding to the location of hole 356 of the first
plate 320. The hole 370 may be internally threaded. The second
plate 322 may include an optional hole (not shown) corresponding to
the location of hole 352 of the first plate 320, to provide access
for a driver to engage the head of the fastener 324 in hole 352
when the plate sub-assembly 302 is operatively assembled. The
second plate 322 may include an optional bullseye level or tube
level (not shown) for preliminary leveling.
[0109] The fastener 324 may be a countersunk head screw.
[0110] The fastener 326 may be referred to as a windage adjustment
screw. The head of fastener 326 may be adapted for manual
tightening and loosening.
[0111] The fastener 328 may be referred to as a windage lock screw.
The head of fastener 328 may be adapted for manual tightening and
loosening.
[0112] The fastener 330 may be a socket head shoulder bolt with a
threaded tip 372 and a smooth shaft 374 between the tip 372 and the
head. The fastener 330 may be referred to as a windage pivot bolt,
whose central longitudinal axis may be referred to as a pivot
axis.
[0113] The spring plunger 332 may have a cylindrical body 376 and a
spring-loaded pin tip 378. The body 376 may be smooth or externally
threaded.
[0114] The plate sub-assembly 302 may be operatively assembled by
inserting the fastener 324 through the hole 352 of the first plate
320 from top to bottom with the countersunk head in the countersink
and the screw tip protruding from the bottom side of the first
plate; positioning the second plate 322 on top of the first plate
320 with the front ends 312 facing the same direction, the right
sides 316 facing the same direction, and the top sides facing the
same direction; inserting the fastener 330 through the hole 360
from top to bottom and threading the tip 372 into the hole 350;
press-fitting the top end of the pin 334 in the hole 368 so that
the bottom end of the pin 334 protrudes from the bottom side of the
second plate 322 and into the hole 354; inserting the fastener 328
through the hole 356 from bottom to top and threading the tip into
the hole 370; inserting the spring plunger 332 into the left
portion of the hole 358 so that the tip 378 is against the left
side of the pin 334; and threading the fastener 326 into the right
portion of the hole 358 so that the tip is against the right side
of the pin 334.
[0115] When the plate sub-assembly 302 is operatively assembled,
clockwise and counterclockwise rotation of the fastener 326 causes
the second plate 322 to rotate, or pivot, relative to the first
plate 320 about the fastener 330, against the resistance provided
by the spring plunger 332; and clockwise and counterclockwise
rotation of the fastener 328 locks and unlocks the rotation of the
second plate relative to the first plate. Referring to FIG. 38, the
fastener 326, pin 334, and spring plunger 332 function together as
a windage fine adjustment mechanism. FIG. 38 illustrates the radius
of the arc along which the pin 334 travels as the second plate 322
rotates relative to the first plate 320. The bottom end of the pin
334 may be received in the hole 354 with clearance, which may be
provided all around or only along the right-left direction. The
plate sub-assembly 302 may include indicia (not shown) to indicate
the magnitude of adjustment right or left of a neutral (zero)
position. The fastener 328 and pin 334 are centered in the holes
356, 354, respectively, when the plate sub-assembly is in the
neutral position. The neutral position is illustrated in FIG. 36.
The fastener 328 in hole 356 and/or the pin 334 in hole 354 limit
the range of motion or magnitude of windage adjustment provided by
the plate sub-assembly 302.
[0116] The adapter block base sub-assembly 304 may include a body
340, fasteners 342, 344, and pins 346, 348.
[0117] The body 340 includes an undercut channel 380 which extends
across the top side between the front and back ends 312, 314. The
undercut channel 380 may be a dovetail slot, T-slot, or other
undercut geometry. The undercut channel 380 may be open (extend
through) the front and/or back ends 312, 314. Three holes 382, 384,
386 extend through the body 340 along a top-bottom direction,
centrally located in the right-left width of the undercut channel
380, in a linear arrangement from front to back. The hole 382 is
near the front end 312, corresponding to the location of hole 362
of the second plate 322. The hole 384 is near the middle,
corresponding to the location of hole 364 of the second plate. The
hole 386 is near the back end 314, corresponding to the location of
hole 366 of the second plate. The hole 384 may be internally
threaded or non-threaded (smooth). The top end of the hole 384 may
include a counterbore (FIG. 40). A hole 388 extends through the
body 340 along a right-left direction and intersects the undercut
channel 380 between the holes 384, 386. The right and/or left
portions of hole 388 may be internally threaded.
[0118] The fastener 342 may be referred to as a cross screw. The
head of the fastener 342 may be adapted for manual tightening or
loosening.
[0119] The fastener 344 may be a socket head cap screw.
[0120] The adapter block base sub-assembly 304 may be operatively
assembled by fixing the pin 346 in the hole 382 so that the bottom
end of the pin 346 protrudes below the bottom side of the body 340
and the top end of the pin 346 protrudes up into the undercut
channel 380 (see FIGS. 36, 39, and 40); inserting the fastener 344
into the hole 384 from top to bottom so that the head is received
in the counterbore and the tip protrudes below the bottom side of
the body 340; fixing the pin 348 in the hole 386 so that the bottom
end of the pin 348 protrudes below the bottom side of the body 340
and the top end of the pin 348 is even with or recessed below the
undercut channel 380 (see FIG. 40); and inserting the fastener 342
into the hole 388 so that the tip protrudes from the opposite side
of the body 340 from the head (see FIGS. 38 and 39). The fastener
342 is illustrated with the head against the right side 316 and the
tip protruding from the left side 318.
[0121] When the adapter block base sub-assembly 304 is operatively
assembled, the fastener 342 may be inserted into and removed from
the hole 388 by a user. One or more of the fasteners 342, 344 and
pins 346, 348 may be captive to the body 340.
[0122] The plate sub-assembly 302 and the adapter block base
sub-assembly 304 may be operatively assembled by inserting the
bottom end of pin 346 into the hole 362; inserting the tip of the
fastener 344 into the hole 364, for example by threading the
fastener 344 into the hole 364; and inserting the bottom end of pin
348 into the hole 366. The pin 346 and holes 382, 362 may be a
different diameter than the pin 348 and holes 386, 366; or the
bottom end of pin 346 may protrude below the bottom side of the
body 340 a different distance than the bottom end of pin 348; so
that the plate sub-assembly 302 and the adapter block base
sub-assembly 304 may only be assembled in a single orientation with
the front ends 312 facing the same direction, the right sides 316
facing the same direction, and the top sides facing the same
direction.
[0123] When the plate sub-assembly 302 and the adapter block base
sub-assembly 304 are operatively assembled, the second plate 322
and the body 340 are rigidly secured together and mutually aligned
along a front-back line extending through the holes 362, 364, 366,
382, 384, 386.
[0124] Returning to FIG. 36, the adapter block 306 may be adapted
to couple to the illustrated receiver 200. The adapter block 306
includes an undercut rail 390 which extends across the bottom side
between the front and back ends 312, 314. The undercut rail 390 may
be a dovetail rail, T-rail, or other undercut geometry, and is
preferably complementary to the undercut channel 380 of the body
340 of the adapter block base sub-assembly 304. The undercut rail
390 may extend across the entire bottom side, or a portion. A hole
392 may extend through the adapter block 306 along a top-bottom
direction and may be located in a front half of the adapter block
306. The hole 392 may be internally threaded to correspond to the
external threads of the front guard screw for the receiver 200. A
notch 394 may extend across the top back end of the adapter block
306 along a right-left direction to form a step down from the top
side. The notch 394 may have a 90 degree internal corner.
[0125] The adapter block assembly 308 may be adapted to couple
directly to a scope 500, without the first assembly 100 or receiver
200. Preferably, the adapter block assembly 308 may couple to a
1'', 30 mm, or 34 mm scope. The adapter block assembly 308 may
include a bottom block 702 and a top block 704. Optional fasteners
(not shown) may be included with the adapter block assembly 308.
This enables a shooter to test whether the scope 500 by itself has
accurate come up adjustment or elevation adjustment, which may be
of interest in military or other specialized shooting
situations.
[0126] The bottom block 702 includes an undercut rail 706 which
extends across the bottom side between the front and back ends 312,
314. The undercut rail 706 may be a dovetail rail, T-rail, or other
undercut geometry, and is preferably complementary to the undercut
channel 380 of the body 340 of the adapter block base sub-assembly
304. The undercut rail 706 may extend across the entire bottom
side, or a portion. A V-groove 708 extends across the top side
between the front and back ends 312, 314. A tab 710, or ear, may
protrude from the top right side of the bottom block 702; a mirror
image tab 712 may protrude from the top left side of the bottom
block 702 (FIG. 49). A hole 714 may extend through the tab 710
along a top-bottom direction and may include internal threads; an
identical hole (not visible) may extend through the tab 712.
[0127] The top block 704 includes a V-groove 718 that extends
across the bottom side between the front and back ends 312, 314. A
tab 720, or ear, may protrude from the bottom right side of the top
block 704; a mirror image tab 722 may protrude from the bottom left
side of the top block 704 (FIG. 49). A hole 724 may extend through
the tab 720 along a top-bottom direction and may include internal
threads or may be smooth; an identical hole 726 (FIG. 49) may
extend through the tab 722.
[0128] The adapter block assembly 308 may be operatively assembled
by orienting the bottom and top blocks 702, 704 with the front ends
312 facing the same direction, the right sides 316 facing the same
direction, and the top sides facing the same direction, so that the
V-grooves 708, 718 face each other, the tabs 710, 720 face each
other, and the tabs 712, 722 face each other. Fasteners (not
shown), such as screws, may be inserted through the holes in the
tabs to lock the bottom and top blocks 702, 704 together.
[0129] The adapter block 310 may be adapted to couple to a standard
Remington 700 or round clone receiver. The round receiver is held
rigidly in the V block 310 so that the action will not roll right
or left as the scope is being leveled, as discussed below. The
adapter block 310 includes an undercut rail 728 which extends
across the bottom side between the front and back ends 312, 314.
The undercut rail 728 may be a dovetail rail, T-rail, or other
undercut geometry, and is preferably complementary to the undercut
channel 380 of the body 340 of the adapter block base sub-assembly
304. The undercut rail 728 may extend across the entire bottom
side, or a portion. A V-groove 730 extends across the top side
between the front and back ends 312, 314. A hole 732 may extend
through the adapter block 310 along a top-bottom direction and may
be located in a front half of the adapter block 310. The hole 732
may be internally threaded to correspond to the external threads of
the front guard screw for the standard Remington 700 or round clone
receiver. Other action blocks are contemplated for various actions,
each including a hole to receive the corresponding front guard
screw. Referring to FIG. 40, a notch 734 may extend into the bottom
front end of the adapter block 310. The notch 734 may be sized,
shaped, and located to receive the top end of the pin 346. A
transverse groove 736 may extend across the bottom side of the
adapter block 310 between the right and left sides 316, 318 in the
rear half of the adapter block. The groove 736 may be sized,
shaped, and located to receive a portion of the fastener 342.
[0130] Referring to FIGS. 39-40, each adapter block may be
interchangeably operatively assembled to the adapter block base
sub-assembly 304. The adapter block 310 is shown as an example. The
adapter block 310 may be operatively assembled to the adapter block
base sub-assembly 304 by sliding the front end of the undercut rail
728 into the back end of the undercut channel 380 of the body 340
of the adapter block base sub-assembly 304 until the top end of the
pin 346 enters the notch 734 and inserting the fastener 342 through
the hole 388 and the groove 736.
[0131] When the adapter block 310 is operatively assembled to the
adapter block base sub-assembly 304, the adapter block 310 is
rigidly secured to the adapter block base sub-assembly and aligned
along a front-back line extending through the holes 382, 384,
386.
[0132] Returning to FIG. 36, the rifle bench rest 400 may be a
prior art apparatus such as those marketed by Sinclair, Hart, and
Wichita. Not every part or feature of the rifle bench rest 400 will
be described. The rifle bench rest 400 may include a main column
402 (FIG. 45) and three adjustable feet 410, 412, 414 (FIG. 51).
The main column 402 may be replaced by the main column 404 or the
main column 406. The top end of each main column 402, 404, 406 may
include an internally threaded hole 422 (not visible), 424, 426.
Each foot 410, 412, 414 is adjustable up and down to raise or lower
the foot as needed to make the main column precisely vertical or
achieve other alignment goals.
[0133] Referring to FIG. 41, the adapter block 306, adapter block
base sub-assembly 304, plate sub-assembly 302, and rifle bench rest
400 are shown operatively assembled together.
[0134] Referring to FIGS. 42 and 43, the receiver 200 may be
operatively assembled to the adapter block 306 by placing the
bottom surface 216 of the receiver 200 against the top side of the
adapter block 306 with the front ends 210, 312 facing the same way
and inserting the front guard screw for the receiver 200 through
the hole 392 and into the hole 218. The receiver 200 and adapter
block 306 may then be operatively assembled to the adapter block
base sub-assembly 304. The adapter block base sub-assembly 304,
plate sub-assembly 302, and rifle bench rest 400 may already be
operatively assembled together. FIG. 43 shows that the fastener 330
is preferably centered under the receiver axis 214 so that the axis
214 intersects the pivot axis of the fastener 330. FIG. 45 shows
that the foot 410 of the rifle bench rest 400 is preferably
centered under the receiver axis 214. The first assembly 100 may be
operatively assembled to the receiver 200 at any step in this
procedure, preferably after the receiver 200, adapter block 306,
adapter block base sub-assembly 304, plate sub-assembly 302, and
rifle bench rest 400 have been assembled. FIG. 43 shows a barrel,
in dashed lines, coupled to the receiver 200. While not shown for
clarity, the trigger assembly, ejector, and/or other assemblies and
parts normally coupled to the receiver 200 may remain attached.
However, preferably, the magazine well assembly and stock are
removed.
[0135] Similarly, the standard Remington 700 or round clone
receiver may be operatively assembled to the adapter block 310 by
placing the bottom side of the action in the V-groove 730 with the
front ends facing the same way and inserting the front guard screw
for the action through the hole 732 and into the front guard screw
hole of the action.
[0136] Referring to FIG. 44, after the first assembly 100, receiver
200, adapter block 306, adapter block base sub-assembly 304, plate
sub-assembly 302, and rifle bench rest 400 have been assembled, the
combined apparatus may be positioned with the receiver 200 visually
aimed downrange. The feet 410, 412, 414 of the rifle bench rest 400
may be adjusted up or down until the bubble in the tube level 106
of the first assembly 100 is centered. The feet 410, 412, 414 may
also be adjusted until the bubble in the bullseye level 104 is
centered. When the bubbles in the tube level 106 and/or the
bullseye level 104 are precisely centered, the receiver 200 and its
axis 214 are precisely leveled with respect to Earth's gravity.
Preferably, the feet 410, 412, 414 are adjusted until the bubbles
in the tube level 106 and the bullseye level 104 are simultaneously
precisely centered.
[0137] Referring to FIG. 45, a scope 500 may be coupled to the
precisely leveled receiver 200. The scope 500 is shown
schematically in this figure. The scope 500 may be coupled to the
receiver 200 before the receiver has been precisely leveled. Either
way, at this stage, the scope 500 is preferably coupled to the
receiver 200 loosely enough that the scope may be reoriented
relative to the receiver. A target 600 may be mounted to a target
frame (not shown) and set up downrange, for example, at 100 yards,
200 yards, 500 yards, 1000 yards, etc. Preferably, the target 600
may be mounted to the frame with reference to a plumb line or other
true vertical datum (not shown) so that vertical indicia 602 on the
target 600 are precisely vertical. A plumb line may be used instead
of the target 600.
[0138] Elevation at the downrange target 600 may be adjusted at
foot 410, which is preferably in the rear and centered under the
central longitudinal axis 214 of the receiver 200. As the vertical
reticle image can span about 48'' at 100 yards or meters, and the
height of the target image downrange can also vary, the rear post
adjustment screw (foot 410) is a practical means for elevation
adjustment. Elevation may be adjusted while viewing the target 600
through the scope 500. Preferably, elevation is adjusted so that
the horizontal reticle is even with the center point of the
target.
[0139] Windage at the target 600 may be adjusted using the plate
sub-assembly 302, preferably without repositioning the rifle bench
rest 400, preferably without repositioning the feet 410, 412, 414.
Fastener 326 may be turned clockwise and counterclockwise to adjust
windage while viewing the target 600 through the scope 500.
Preferably, windage is adjusted so that the vertical reticle is
even with the center point of the target. At this stage, the
vertical and horizontal reticles may not be truly vertical and
horizontal, but their intersection is superimposed over the center
point of the target. Fastener 328 may be tightened to lock the
plate sub-assembly 302 when windage is precisely adjusted, or
loosened to permit further windage adjustment. The illustrated
plate sub-assembly 302 provides over 18'' of right to left
horizontal adjustment or correction at 100 yards or meters.
[0140] The scope 500 may be rotated right or left to align its
vertical reticle to a vertical datum at the target 600, such as a
plumb line, a 4 foot sheet rock level, a commercial target, a laser
generated line, or a target having two closely-spaced vertical
indicia 602. The scope 500 may be rotated while viewing the target
600 through the scope. Preferably, the receiver 200 remains
precisely leveled while the scope 500 is rotated. After the
vertical reticle is precisely aligned to the vertical datum at the
target 600, the scope 500 may be tightly secured to the receiver
200. This may involve multiple iterations of incrementally
tightening the scope fittings, checking the alignment of the
vertical reticle by viewing the vertical datum through the scope,
checking the levels 104, 106, and rotating the scope to realign the
vertical reticle to the vertical datum.
[0141] While the preceding steps of elevation adjustment, windage
adjustment, and scope rotation are described in an order, the steps
may be performed in any order and any step may be performed more
than once during scope alignment.
[0142] After the scope has been aligned and tightly secured to the
receiver 200, a scope level (not shown) may be attached, aligned so
that its bubble is centered, and fixed to the aligned scope 500.
Performing this step at this stage may ensure that the scope level
is actually "true," i.e., the scope level bubble is centered when
the scope 500 and receiver 200 are truly level. The scope level may
then be relied upon in the field when aiming in on a target.
[0143] Referring to FIGS. 46-48, the adapter block 310, adapter
block base sub-assembly 304, plate sub-assembly 302, and rifle
bench rest 400 are shown operatively assembled together.
[0144] Referring to FIG. 49, the adapter block assembly 308,
adapter block base sub-assembly 304, plate sub-assembly 302, and
rifle bench rest 400 are shown operatively assembled together.
[0145] Referring to FIGS. 50-52, the scope 500 is shown operatively
assembled in the adapter block assembly 308. This arrangement
enables a scope to be evaluated for accurate movement in response
to scope turret actuation. In other words, this arrangement tests a
scope for accurate elevation (come up) and/or windage
adjustment.
[0146] Referring to FIG. 53, a bottom side of an AR action 750 is
shown. The AR action includes a receiver 752 having a planar bottom
surface 754, a front takedown boss 756, a rear takedown boss 758,
and a chamber 764. The bottom surface 754, particularly between the
front and rear takedown bosses 756, 758, is a reliable precision
machined planar surface which is an excellent primary datum feature
for the disclosed technology. The bottom surface 754 between the
front and rear takedown bosses 756, 758 may be referred to as a
planar datum surface. The front takedown boss 756 includes a front
takedown hole 760 and the rear takedown boss 758 includes a rear
takedown hole 762. The chamber 764 is a cavity which extends into
the receiver 752 from the bottom side. The AR action also includes
a rear takedown pin 766, visible in FIG. 54. Many variants now
exist based upon the original ArmaLite design: AR-10, AR-15, M1,
M4, M16, etc. In 2009, the term "modern sporting rifle" was coined
by the National Shooting Sports Foundation to describe modular
semi-automatic rifles including AR-15s. Today, nearly every major
firearm manufacturer produces its own generic AR-15 style
rifle.
[0147] Referring to FIGS. 54-61, the AR action 750 is shown coupled
to a scope 770. A third assembly 800 may be an adaptation of the
principles disclosed above for the first and second assemblies 100,
300, specific to the AR action 750. The third assembly 800 may thus
be referred to as an AR sighting holder or AR sighting assembly.
The third assembly 800 may include an adapter block 802 which
functions like the adapter blocks 306, 308, 310 to securely couple
to the AR receiver 752, and a plate sub-assembly 804 which
functions like the plate sub-assembly 302. The third assembly 800
is shown coupled to the rifle bench rest 400.
[0148] The adapter block 802 functions like the adapter blocks 306,
308, 310 to securely couple the AR receiver 752 to the plate
sub-assembly 804. The adapter block 802 includes front, rear,
right, left, top, and bottom sides 810, 812, 814, 816, 818, 820. A
transverse notch 822 may extend from right to left across the front
side 810 and the top side 818 to provide clearance for the front
takedown boss 756 of the receiver 752 when the bottom surface 754
is against the top side 818. A boss 824 may extend upwardly from
the top side 818. The boss 824 may be sized, shaped, and located to
be received within the chamber 764 of the receiver 752, preferably
within a front region of the chamber 764 near the front takedown
boss 756. A substantially rectangular boss 824 is illustrated. The
boss 756 may fit within the chamber 764 with generous front and
back clearance and little to no right and left clearance. A slot
826 may extend into the top side 818, and may be sized, shaped, and
located to receive the rear takedown boss 758 of the receiver 752
when the bottom surface 754 is against the top side 818. The slot
826 may include generous front and back clearance and little to no
right and left clearance relative to the rear takedown boss 758. A
transverse hole 828 may extend from right to left through the
adapter block 802 and crossing the slot 826. The hole 828 may be
sized, shaped, and located to receive the rear takedown pin 766
when the bottom surface 754 is against the top side 818 and the
rear takedown boss 758 is in the slot 826. Additional transverse
holes 830, 832 are shown in front of and in back of the hole 828;
the additional holes 830, 832 may be provided to accommodate AR
receivers with different rear takedown boss locations. A group of
three holes 834, 836, 838 may extend from top to bottom through the
adapter block 802, which may function like the group of holes 382,
384, 386 of the body 340 of the adapter block base sub-assembly 304
to receive fastener 344 and pins 346, 348 to couple the adapter
block 802 to the plate sub-assembly 804. The holes 834, 836, 838
are shown extending through the boss 824 in this example. A hole
840 may extend from top to bottom through the adapter block 802, to
the rear of hole 838. The hole 840 may receive a fastener to
further couple the adapter block 802 to the plate sub-assembly 804.
Referring to FIG. 56, the adapter block 802 may include the
bullseye level 104 secured by the screws 114, 116, 118 and the tube
level 106 secured by the set screws 120, 122, as described for the
first assembly 100.
[0149] The plate sub-assembly 804 functions like the plate
sub-assembly 302, including coupling to the main column 402 of the
rifle bench rest 400, coupling to the adapter block 802, and
providing a windage fine adjustment mechanism. The plate
sub-assembly 804 may include a first plate 850 and a second plate
852, and may use fasteners 324, 326, 328, 330, spring plunger 332,
and pin 334. The first plate 850 may be referred to as a lower
plate and the second plate 852 may be referred to as a top plate.
The first plate 850 may couple to the rifle bench rest 400. The
second plate 852 may couple to the adapter block 802. The first
and/or second plate 850, 852 may include an optional bullseye level
or tube level (not shown) for preliminary leveling. The plate
sub-assembly 804 may be operatively assembled by a method similar
to that described above for the plate sub-assembly 302.
[0150] Referring to FIGS. 54-55, the receiver 752 may be
operatively assembled to the adapter block 802 by orienting the
receiver and adapter block with the front ends facing the same way,
and the bottom surface 754 of the receiver facing the top side 818
of the adapter block; inserting the rear takedown boss 758 into the
slot 826; aligning the rear takedown hole 762 with the hole 828;
inserting the rear takedown pin 766 through the holes 762, 828;
inserting the boss 824 into the chamber 764; receiving the front
takedown boss 756 in the notch 822; and placing the bottom surface
754 against the top side 818. The steps of inserting the rear
takedown boss 758 into the slot 826, aligning the rear takedown
hole 762 with the hole 828, and inserting the rear takedown pin 766
through the holes 762, 828 may be performed with the front end of
the receiver 752 tilted up as shown. The nominal dimensions and
tolerances between the receiver 752 and adapter block 802 may be
selected so that when the receiver is assembled to the adapter
block, the bottom surface 754 is in surface contact with the top
side 818, in other words, has at least three points of mutual
contact. Thus, the top side 818 may function as a primary planar
datum surface of the adapter block 802. While this description is
made in the context of a continuous flat planar top side 818, it is
contemplated that the top side 818 may instead comprise
discontinuous patches, or points, for contacting the bottom surface
754. Taken together, the discontinuous patches or points may
function as a primary planar datum surface. Whether the top side
818 is continuous or discontinuous, the top side 818 preferably
contacts the full length of the bottom surface 754 between the
between the front and rear takedown bosses 756, 758.
[0151] The adapter block 802 may be operatively assembled to the
plate sub-assembly 804 by a method similar to that described for
the adapter block 310, the adapter block base sub-assembly 304, and
the plate sub-assembly 302, modified of course due to the adapter
block 802 incorporating features of the adapter block base
sub-assembly 304.
[0152] The methods of using the third assembly 800 to first
precisely level the AR receiver 752 and then precisely level the
reticles of the scope 770 are according to the principles laid out
above for the first and second assemblies 100, 300.
[0153] All parts of the apparatus described herein are preferably
fabricated from substantially rigid materials, for example metals
or ceramics, except for parts that are described as compliant,
elastic, deformable, springs, and the like.
[0154] Any methods disclosed herein includes one or more steps or
actions for performing the described method. The method steps
and/or actions may be interchanged with one another. In other
words, unless a specific order of steps or actions is required for
proper operation of the embodiment, the order and/or use of
specific steps and/or actions may be modified.
[0155] Reference throughout this specification to "an embodiment"
or "the embodiment" means that a particular feature, structure or
characteristic described in connection with that embodiment is
included in at least one embodiment. Thus, the quoted phrases, or
variations thereof, as recited throughout this specification are
not necessarily all referring to the same embodiment.
[0156] Similarly, it should be appreciated that in the above
description of embodiments, various features are sometimes grouped
together in a single embodiment, figure, or description thereof for
the purpose of streamlining the disclosure. This method of
disclosure, however, is not to be interpreted as reflecting an
intention that any claim require more features than those expressly
recited in that claim. Rather, as the following claims reflect,
inventive aspects lie in a combination of fewer than all features
of any single foregoing disclosed embodiment. Thus, the claims
following this Detailed Description are hereby expressly
incorporated into this Detailed Description, with each claim
standing on its own as a separate embodiment. This disclosure
includes all permutations of the independent claims with their
dependent claims.
[0157] Recitation in the claims of the term "first" with respect to
a feature or element does not necessarily imply the existence of a
second or additional such feature or element. Elements recited in
means-plus-function format are intended to be construed in
accordance with 35 U.S.C. .sctn. 112 Para. 6. It will be apparent
to those having skill in the art that changes may be made to the
details of the above-described embodiments without departing from
the underlying principles of the technology.
[0158] While specific embodiments and applications of the present
technology have been illustrated and described, it is to be
understood that the technology is not limited to the precise
configuration and components disclosed herein. Various
modifications, changes, and variations which will be apparent to
those skilled in the art may be made in the arrangement, operation,
and details of the methods and systems of the present technology
disclosed herein without departing from the spirit and scope of the
technology.
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