U.S. patent application number 11/047019 was filed with the patent office on 2005-09-01 for barrel assembly and attachment system.
Invention is credited to Stone, Jeffrey W..
Application Number | 20050188591 11/047019 |
Document ID | / |
Family ID | 34889751 |
Filed Date | 2005-09-01 |
United States Patent
Application |
20050188591 |
Kind Code |
A1 |
Stone, Jeffrey W. |
September 1, 2005 |
Barrel assembly and attachment system
Abstract
A receiver and barrel assembly is provided. The barrel is
readily removed from the receiver. Additionally, the head space of
the assembly is readily adjusted. These features provide improved
manufacturability and customized use of the rifle.
Inventors: |
Stone, Jeffrey W.;
(Elizabethtown, KY) |
Correspondence
Address: |
WOMBLE CARLYLE SANDRIDGE & RICE, PLLC
P.O. BOX 7037
ATLANTA
GA
30357-0037
US
|
Family ID: |
34889751 |
Appl. No.: |
11/047019 |
Filed: |
January 31, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60540360 |
Jan 30, 2004 |
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Current U.S.
Class: |
42/75.02 |
Current CPC
Class: |
F41A 21/485 20130101;
F41A 21/487 20130101 |
Class at
Publication: |
042/075.02 |
International
Class: |
F41A 021/00 |
Claims
What is claimed is:
1. A split receiver for use in a barrel assembly, comprising: a
substantially cylindrical body having an aft end and a fore end,
the body having an axial bore extending from the aft end to the
fore end, and a slot extending from the fore end toward the aft end
of the body; and a clamping screw aligned radially with the
slot.
2. The receiver of claim 1, wherein the clamping screw is
positioned to tighten in a direction substantially perpendicular to
the slot.
3. The receiver of claim 1, further comprising a barrel set screw
proximate the fore end of the receiver, the barrel set screw being
positioned to tighten in a direction substantially perpendicular to
the axial bore of the receiver.
4. The receiver of claim 3, wherein the barrel set screw has a cone
point.
5. The receiver of claim 1, wherein the slot has an open width of
from about 0.025 to about 0.060 in.
6. The receiver of claim 1, wherein the slot has a length of from
about 0.50 to about 1.5 in.
7. The receiver of claim 1, wherein the slot extends to a magazine
chamber formed in the receiver, thereby forming an overall clamping
length of from about 2 to about 4 inches.
8. A barrel attachment system for a firearm comprising: a receiver
having a fore end and an axial bore therethrough; a barrel
including a mating portion dimensioned to be received in the axial
bore; and a clamping screw positioned proximate the fore end of the
receiver.
9. The barrel attachment system of claim 8, wherein the receiver
includes a slot substantially aligned radially with the clamping
screw.
10. The barrel attachment system of claim 9, wherein the slot
extends from the fore end toward the aft end.
11. The barrel attachment system of claim 9, wherein the clamping
screw is positioned so that it tightens in a direction
substantially perpendicular to the slot.
12. A firearm comprising: a receiver having a fore end, an aft end,
an axial bore therethrough, and a slot extending from the fore end
towards the aft end; a barrel including a mating portion having a
breach face, the mating portion slidably received within the axial
bore; and a securing means positioned at the fore end of the
receiver and substantially aligned radially with the slot, wherein
the securing means permits the barrel to be secured at a desired
position within the receiver to achieve a desired head space.
13. The firearm of claim 12, wherein the securing means comprises a
clamping screw that tightens in a direction substantially
perpendicular to the axial bore.
14. The firearm of claim 12, wherein the securing means comprises a
clamping screw positioned proximate the fore end of the receiver
and substantially perpendicularly aligned with the slot, whereby
the clamping screw tightened against the barrel forms a taper in
the receiver against the mating portion of the barrel.
15. The firearm of claim 12, further comprising a bolt assembly
dimensioned to be received in the axial bore at the aft end of the
receiver, the bolt assembly including a bolt face, wherein a
minimum head space is defined by engaging the breach face of the
barrel with the bolt face.
16. A method of assembling a receiver and barrel, comprising:
providing a receiver having an axial bore therethrough and a slot
having an open width; inserting a mating portion of a barrel into
the axial bore; and tightening a securing means substantially
radially aligned with the slot, wherein tightening the securing
means decreases the open width of the slot and deforms the receiver
toward and against the barrel.
17. The method of claim 16, wherein the mating portion of the
barrel is inserted into the axial bore to an extent needed to
achieve a desired head space.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application Ser. No. 60/540,360, filed Jan. 30, 2004, which is
incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to firearms, and in
particular, to the assembly of a barrel and receiver and a method
to set and maintain the head space of a bolt and barrel breach
interface.
BACKGROUND OF THE INVENTION
[0003] Manufacturers of firearms constantly seek improvements in
the way firearms are manufactured. Specifically, manufacturers seek
enhanced manufacturability and process control to optimize quality
and production quality. At the same time, the end-user seeks
customization and ease of repair and replacement of parts of the
firearm. Thus, there is a need for a firearm design that enhances
manufacturability and process control, while simplifying
customization and repair.
SUMMARY OF THE INVENTION
[0004] The present invention generally is directed to a receiver
and barrel assembly for a firearm, such as a rifle or other long
gun or other types of firearms, and a method for assembling and
attaching the barrel and receiver and setting the head space
between the bolt and the barrel. According to the present
invention, the firearm readily is assembled at the time of
manufacture, and readily disassembled as needed or desired to meet
the needs of the individual shooter, without the need for special
tooling or equipment.
[0005] According to one aspect of the present invention, a split
receiver for use in the barrel assembly of the present invention
comprises a substantially cylindrical body having an aft end and a
fore end. The body of the receiver has an axial bore extending
therethrough from the aft end to the fore end, and a slot extending
from the fore end toward the aft end of the body.
[0006] The receiver also comprises a set screw or clamping screw
aligned radially with the slot. The clamping screw may be
positioned to tighten in a direction substantially perpendicular to
the slot. The receiver also may include a barrel set screw
proximate the fore end of the receiver. The barrel set screw may be
positioned to tighten in a direction substantially perpendicular to
the axial bore of the receiver. The barrel set screw may have a
cone point that marks the barrel upon tightening.
[0007] A barrel comprising a mating portion dimensioned to be
received in the axial bore engages the open fore end of the
receiver. In this position, the receiver can engage and secure the
barrel into the receiver by tightening the clamping screw and the
barrel set screw at a desired head space. Upon tightening the
clamping screw and barrel set screw, a taper is formed in the
receiver at the fore end, thereby securing the barrel and the
receiver.
[0008] According to another aspect of the present invention, a
method of assembling a receiver and barrel is provided. The method
includes providing a receiver having an axial bore therethrough and
a slot having an open width, inserting a mating portion of a barrel
into the axial bore, and tightening a securing means substantially
radially aligned with the slot. The mating portion of the barrel is
inserted into the axial bore to an extent needed to achieve a
desired head space. Tightening the securing means then decreases
the open width of the slot and deforms the receiver toward and
against the barrel.
[0009] Various features, objects, and advantages of the present
invention are discussed in, or are apparent from, the detailed
description and accompanying drawings set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a partially exploded side plan view of an
exemplary firearm that may include a receiver and barrel assembly
according to the present invention.
[0011] FIG. 2 is an exploded perspective view of an exemplary
receiver and barrel assembly according to the present
invention.
[0012] FIG. 3 is an alternate exploded perspective view of an
exemplary receiver and barrel assembly according to the present
invention.
[0013] FIG. 4 is a bottom plan view of an exemplary assembled
receiver and barrel according to the present invention.
[0014] FIG. 5 is a side plan view of an exemplary assembled
receiver and barrel according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] In contrast to presently available barrel assemblies, the
present invention includes features that improve manufacturability
and customization of a firearm. In particular, the features
simplify manufacturing and permit rapid barrel replacement and head
space adjustment without the need for special tooling or equipment.
The present invention as described herein typically is used for
rimfire rifle barrel attachment systems, but may be used with other
long guns or other types of firearms.
[0016] As shown in FIGS. 1-3, the barrel assembly 10 of the present
invention generally includes a receiver 15 and a barrel 20 used in
connection with a firearm, for example, a rifle F, shown in
exploded view in FIG. 1. The receiver 15 has a substantially
cylindrical body 22 having a first or aft end 25, a second or fore
end 30, and an axial bore 35 extending therethrough from the aft
end 25 to the fore end 30. The receiver 15 also includes a slot 40
having an open width W extending a length L from the fore end 30
toward the aft end 25 of the body 22. The open width W and length L
vary for a given receiver design. In one aspect, the open width W
is from about 0.025 in. to about 0.060 in., for example 0.040 in.
In another aspect, the slot 40 has a length from about 0.5 in. to
about 1.5 in. for example, 1 inch.
[0017] The receiver also includes a clamping screw 38, set screw,
locking pin, or other securing means proximate the fore end 30 of
the receiver 15 for releasably securing the barrel 20 within the
receiver 15. The clamping screw 38 is substantially aligned
radially with the slot 40 and tightens in a direction substantially
perpendicular to the axial bore 35. In one aspect, the clamping
screw 38 is aligned in a substantially perpendicular relation to
the slot 40.
[0018] The receiver further includes a barrel set screw 48,
typically tightened at the time of manufacture. The barrel set
screw 48 is positioned so that it tightens in a radial direction,
substantially perpendicular to the axial bore 35. In one aspect,
the barrel set screw 48 is a cone point screw, so that upon
tightening against the barrel 20, the mating portion 55 of the
barrel 20 is marked or scored permanently. The marking then can be
used to determine whether the barrel 20 has been tampered with
after assembly. According to one aspect of the present invention,
the slot 40 is extended to a magazine chamber 70, thereby providing
an overall clamping length L' (FIG. 4) of from about 2 inches to
about 4 inches, for example, about 3 inches. By doing so, the body
22 of the receiver 15 more readily deforms during assembly, thereby
requiring less torque to tighten the barrel set screw 48.
[0019] The receiver 15 also may include a guide pin 45 (best seen
in FIG. 4) that extends inward from the exterior of the receiver 15
into the axial bore 35. The guide pin 45 may be mounted flush to
the exterior of the receiver 15 and may extend into the bore 35
about 0.05 in. to about 0.10 in., although greater or lesser
amounts of extension of the guide pin also can be used as needed or
desired.
[0020] Still viewing FIGS. 1-3, the barrel 20 includes a first end
75 defining a mating portion 55 with a mating shoulder 60 formed
thereabout, and a second, distal end 80. The mating portion 55 is
dimensioned to be slidably received in the axial bore 35 of the
receiver 15. The barrel 20 also may include a guide groove (not
shown) or similar directional feature dimensioned to slidably
receive the guide pin 45 of the receiver 15. It should be noted
that different barrels having different length mating portions also
can be provided or used.
[0021] To assemble the receiver 15 and barrel 20, the mating
portion 55 of the barrel 20 is rotated as needed to align the guide
groove 65 and the guide pin 45 of the receiver 15. The mating
portion 55 then is slidably inserted into the axial bore 35 of the
receiver 15. A bolt assembly 85 is inserted into the receiver 15
and closed. The bolt assembly 85 includes a bolt face 90 having a
counterbore (not shown) therein.
[0022] According to the present invention, the barrel 20 is
slidably adjusted within the axial bore 35 of the receiver 15 along
the length thereof until a desired head space is attained. The
minimum possible head space is attained by bringing the barrel
breach face 105 into contact with the counterbore of the bolt face
90 within the receiver 15. Hard gauging techniques known to those
of skill in the art can be used to attain a greater head space if
desired.
[0023] The ability to adjust the head space in this manner provides
significant advantages over presently available receiver and barrel
assemblies. Notably, the receiver and assembly of the present
invention readily accommodate normal tolerance variations in the
barrel and receiver, thereby simplifying the manufacturing process.
Additionally, secondary machining typically required to provide a
proper engagement of the receiver and barrel is not required.
[0024] Turning to FIGS. 4 and 5, when the barrel 20 is positioned
relative to the receiver 15 at the desired head space, the clamping
screw 38 is tightened. The tightening action causes the open width
W of the slot to decrease. Further, the tightening action causes
the fore end 30 of the receiver 15 to deform toward and against the
mating portion 55 of the barrel 20, thereby forming a taper in the
receiver 15. The taper in the receiver decreases the diameter of
the receiver 15 at the fore end 30 relative to the original
diameter. Depending on the particular firearm, a required torque
may be specified. In one aspect, the required torque on the
clamping screw is from about 100 in-lbf to about 125 in-lbf. The
resulting taper helps to substantially securely clamp the receiver
15 to the barrel 20 seated therein. Additionally, tightening of the
clamping screw 38 maintains the desired head space dimension.
[0025] Assembly of the barrel 20 and receiver 15 of the firearm F
is completed by tightening the barrel set screw 110, which further
helps to secure the barrel 20 in the receiver 15. In one aspect,
the barrel set screw 110 requires a minimum torque setting of at
least about 25 in-lbf. Tightening the barrel set screw 110 in this
manner may provide from about 500 lb to about 1000 lb of additional
force in securing the barrel 20 in the receiver 15.
[0026] In contrast to presently known, more complicated assemblies,
only two screws or other securing means are needed to secure the
receiver to the barrel. Thus, the simple, easy to use design of the
present invention permits the assembly to be customized according
to the preferences of the user. Additionally, the present invention
allows a damaged or worn barrel and/or receiver to be replaced with
little effort or cost.
[0027] Accordingly, it will be readily understood by those persons
skilled in the art that, in view of the above detailed description
of the invention, the present invention is susceptible of broad
utility and application. Many adaptations of the present invention
other than those herein described, as well as many variations,
modifications, and equivalent arrangements will be apparent from or
reasonably suggested by the present invention and the above
detailed description thereof, without departing from the substance
or scope of the present invention.
[0028] While the present invention is described herein in detail in
relation to specific aspects, it is to be understood that this
detailed description is only illustrative and exemplary of the
present invention and is made merely for purposes of providing a
full and enabling disclosure of the present invention. The detailed
description set forth herein is not intended nor is to be construed
to limit the present invention or otherwise to exclude any such
other embodiments, adaptations, variations, modifications, and
equivalent arrangements of the present invention, the present
invention being limited solely by the claims appended hereto and
the equivalents thereof.
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