U.S. patent application number 16/191805 was filed with the patent office on 2020-01-23 for adjustable gas block assembly for a gas operated semi-automatic firearm.
The applicant listed for this patent is Springfield, Inc.. Invention is credited to Christopher Martin Baumbach, Charles David Williams.
Application Number | 20200025477 16/191805 |
Document ID | / |
Family ID | 69161039 |
Filed Date | 2020-01-23 |
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United States Patent
Application |
20200025477 |
Kind Code |
A1 |
Williams; Charles David ; et
al. |
January 23, 2020 |
ADJUSTABLE GAS BLOCK ASSEMBLY FOR A GAS OPERATED SEMI-AUTOMATIC
FIREARM
Abstract
Adjustable gas block assemblies for gas-operated firearms are
disclosed along with modes of operation and methods of use. In
certain aspects, gas blocks having a vent opening arranged to
receive a vent plug are disclosed, the vent plug having an opening
along a length thereof to vent high-pressure gas from the gas
block. Kits containing multiple vent plugs and, in some instances,
gas blocks are also disclosed.
Inventors: |
Williams; Charles David;
(Geneseo, IL) ; Baumbach; Christopher Martin;
(LeClaire, IA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Springfield, Inc. |
Geneseo |
IL |
US |
|
|
Family ID: |
69161039 |
Appl. No.: |
16/191805 |
Filed: |
November 15, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62586554 |
Nov 15, 2017 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F41A 5/28 20130101; F41A
3/66 20130101 |
International
Class: |
F41A 5/28 20060101
F41A005/28; F41A 3/66 20060101 F41A003/66 |
Claims
1. A method of tuning the gas block assembly of claim 4,
comprising: firing a cartridge in the firearm with the gas block
assembly having the vent plug, which is a first vent plug,
positioned within the vent opening; determining whether the firearm
properly extracted and ejected the cartridge and chambered a new
cartridge or locked a bolt of the firearm in an open configuration;
replacing the first vent plug of the gas block assembly with a
second vent plug having an opening extending along a length
thereof, wherein the opening of the first vent plug has a different
hydraulic diameter than the opening of the second vent plug; and
firing a cartridge in the firearm with the gas block assembly
having the second vent plug positioned within the vent opening.
2. The method of claim 1, wherein the opening of the second vent
plug has a smaller hydraulic diameter than the opening of the first
vent plug.
3. The method of claim 1, wherein the opening of the second vent
plug has a larger hydraulic diameter than the opening of the first
vent plug.
4. A gas block assembly for a firearm, comprising: a gas block
defining a barrel opening, a gas tube opening, a passageway
extending from the barrel opening to the gas tube opening, and a
vent opening intersecting the passageway; and a vent plug received
within the vent opening; wherein the vent plug has an opening
extending along a length of the vent plug and in communication with
the passageway so that high-pressure gas communicating with the
passageway can pass through the opening in the vent plug and out of
the gas block assembly.
5. The gas block assembly of claim 4, wherein the vent plug is
removably received within the vent opening.
6. The gas block assembly of claim 4, wherein the vent plug is
threadably received within the vent opening.
7. The gas block assembly of claim 4, wherein the vent opening is
positioned between the gas tube opening and the barrel opening.
8. The gas block assembly of claim 4, wherein the vent opening
extends from a forward surface of the gas block rearward to the
passageway and wherein the gas tube opening extends from a rearward
surface of the gas block forwardly to the passageway.
9. The gas block assembly of claim 4, wherein the vent plug has a
length sufficient to extend at least partially into the passageway
when received within the vent opening.
10. The gas block assembly of claim 4, wherein the vent opening has
a first cross-sectional dimension adjacent an outer surface of the
gas block and a second cross-sectional dimension adjacent the
passageway and intermediate the passageway and the first
cross-sectional dimension; and wherein the second cross-sectional
dimension is smaller than the first cross-sectional dimension.
11. The gas block assembly of claim 10, wherein the vent plug has a
first end matching the first cross-sectional dimension and a second
end matching the second cross-sectional dimension.
12. The gas block assembly of claim 10, wherein a portion of the
vent opening having the first cross-sectional dimension of the vent
opening is a threaded portion and a portion of the vent opening
having the second cross-sectional dimension is free of threads.
13. An upper assembly for a firearm, comprising: the gas block
assembly of claim 4; an upper receiver; and a barrel attached to
the upper receiver; wherein the gas block assembly is attached to
the barrel.
14. A firearm, comprising: the upper assembly of claim 13 attached
to a lower assembly.
15. A kit, comprising: the gas block assembly of claim 4 wherein
the vent plug is a first vent plug; and a second vent plug for the
gas block; wherein the second vent plug has a length.
16. The kit of claim 15, wherein: the opening of the first vent
plug has a minimum cross-sectional dimension; and the second vent
plug has an orifice extending through the length thereof, the
orifice of the second vent plug having a minimum cross-sectional
dimension less than that of the orifice opening of the first vent
plug.
17. The kit of claim 15, wherein: the second vent plug is free of
an orifice extending through the length thereof.
18. The kit of claim 15, wherein: the length of one of the first or
second vent plugs is greater than the other
19. The kit of claim 18, wherein: the longer vent plug is free of
an orifice.
20. (canceled)
Description
REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S.
Provisional Patent Application No. 62/586,554, filed Nov. 15, 2017,
which is incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present disclosure pertains generally to gas operated
firearms. In particular, the present disclosure pertains to rifles
or pistols having a direct impingement or a gas piston system.
BACKGROUND
[0003] Firearms are very often "chambered" for a particular
caliber, but some firearms are designed to operate (e.g., cycle)
with multiple calibers of ammunition, without causing damage to the
firearm. For example, AR-15 rifles are presently chambered in
5.56x45 NATO, .223 Remington/Wylde, .308 Winchester, or .300
Blackout, just to name a few non-limiting examples. Many AR-15
rifles chambered in 5.56x45 NATO can operate using both 5.56x45
NATO and 0.223 Remington.
[0004] Different calibers of ammunition often have different size
projectiles and/or different powder charges. Ammunition of the same
caliber can even vary in terms of projectile size and powder
charge. For example, projectiles are often provided in full-metal
jacket (FMJ) or jacketed hollow point (JHP) and can be found in
different sizes (e.g., grain). Additionally, manufacturers may use
different quantities and/or types of propellant (i.e., powder) in
their cartridges, which can result in ammunition having different
pressure profiles (e.g., higher maximum pressure) inside the barrel
than another manufacturer's ammunition. This can be due, at least
in part, to the burn rate of the propellant.
[0005] In a gas-operated firearm, a portion of the high-pressure
gas that propels the projectile down the barrel also provides
energy to extract a spent cartridge and to load a new cartridge
into the chamber. In many systems, gas is channeled from a gas port
in the wall of the barrel to a piston and/or through a gas tube
directly to the action of the firearm to move the bolt away from
the barrel chamber. In many instances, a gas block connects the gas
tube to the gas port.
[0006] As may be expected, firearms can operate differently
depending on the caliber and/or ammunition being used. In instances
wherein the energy of the high-pressure gas supplied through the
gas port is significantly more than that necessary to extract a
spent cartridge and load a new cartridge in the chamber, the
firearm may cycle more violently than designed. This can be
uncomfortable to a shooter and, in some instances, may damage the
firearm. In other instances, the energy of the gas supplied through
the gas port is less than that necessary to cycle the firearm,
which may result in the firearm failing to extract a spent
cartridge, load a new cartridge into the chamber, and/or lock the
bolt in an open configuration (e.g., to the rear).
[0007] Adjustable gas blocks such as U.S. Publication No.
2014/0076149 to Adams reduce the volume of gas flowing through the
gas block to the gas tube. Gas blocks of this type, however, can be
difficult and/or time consuming to tune when switching firearm
configurations (e.g., ammunition, muzzle brakes,
suppressed/unsuppressed arrangements, etc.).
SUMMARY
[0008] The present disclosure pertains generally to gas operated
firearms. In particular, the present disclosure pertains to rifles
or pistols having a direct impingement or a gas piston system.
Specifically, the firearms disclosed herein can be AR style
firearms (e.g., AR-15, AR-10, M-16, and M-4), and any of the
methods, assemblies or kits disclosed herein can be used with an AR
style firearm.
[0009] In one exemplary method of tuning an adjustable gas block
assembly of a firearm, the method comprises: firing a cartridge in
the firearm with the gas block assembly having a first vent plug
positioned within a vent opening; determining whether the firearm
properly extracted and ejected the cartridge and chambered a new
cartridge or locked a bolt of the firearm in an open configuration;
replacing the first vent plug of the gas block assembly, the first
vent plug having an opening extending along a length thereof, with
a second vent plug having an opening extending along a length
thereof, wherein the opening of the first vent plug has a different
hydraulic diameter than the opening of the second vent plug; and
firing a cartridge in the firearm with the gas block assembly
having the second vent plug positioned within the vent opening. The
opening of the second vent plug can have a smaller hydraulic
diameter than the opening of the first vent plug or, alternatively,
the opening of the second vent plug can have a larger hydraulic
diameter than the opening of the first vent plug.
[0010] In an exemplary gas block assembly of the present
disclosure, the gas block assembly comprises: a gas block defining
a barrel opening, a gas tube opening, a passageway extending from
the barrel opening to the gas tube opening, and a vent opening
intersecting the passageway; and a vent plug received within the
vent opening; wherein the vent plug has an opening extending along
a length of the vent plug and in communication with the passageway
so that high-pressure gas communicating with the passageway can
pass through the opening in the vent plug and out of the gas block
assembly. The vent plug can be removably received within the vent
opening, and the vent plug can be threadably received within the
vent opening.
[0011] The present disclosure also provides upper assemblies for a
firearm, the upper assembly comprising: any one of the gas block
assemblies disclosed herein; an upper receiver; and a barrel
attached to the upper receiver; wherein the gas block assembly is
attached to the barrel. The present disclosure also provides
firearms, comprising: the upper assembly previously mentioned
attached to a lower assembly.
[0012] Kits containing vent plugs are also disclosed. These kits
may include a first vent plug for a gas block and a second vent
plug for the gas block; wherein the first and second vent plugs
each have a length and at least one of the first and second vent
plugs has an orifice extending through the length thereof. The
first vent plug can have an orifice extending through the length
thereof, the orifice having a minimum cross-sectional dimension;
and the second vent plug can have an orifice extending through the
length thereof, the orifice of the second vent plug having a
minimum cross-sectional dimension less than that of the orifice of
the first vent plug. Alternatively, the first vent plug can have an
orifice extending through the length thereof and the second vent
plug can be free of an orifice extending through the length
thereof. In any of the kits, the length of one of the first or
second vent plugs can be greater than the other. The kits may also
include a gas block having a vent opening arranged to receive the
first or second vent plugs. A gas tube, one or more setscrews,
and/or thread-locking liquid may be provided in any of the kits
disclosed herein.
[0013] Further forms, objects, features, aspects, benefits,
advantages, and embodiments of the present invention will become
apparent from a detailed description and drawings provided
herewith.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of a firearm;
[0015] FIG. 2 is a perspective view of the firearm of FIG. 1 with
the handguard, front sight, and barrel attachment device
removed;
[0016] FIG. 3 is a perspective view of a gas block assembly and a
gas tube;
[0017] FIG. 4 is a perspective view of the gas block assembly and
gas tube of FIG. 3;
[0018] FIG. 5 is an exploded view of the gas block assembly of FIG.
3;
[0019] FIG. 6 is a cross-sectional view of the gas block assembly
on a barrel;
[0020] FIGS. 7A-7E are cross-sectional views of vent plugs;
[0021] FIG. 8 is a cross-sectional view of a gas block assembly on
a barrel with a portion of a vent plug blocking the passageway of
the gas block extending between the gas port and the gas tube;
and
[0022] FIGS. 9-11 are flowcharts illustrating methods of use.
DESCRIPTION OF THE SELECTED EMBODIMENTS
[0023] For the purpose of promoting an understanding of the
principles of the invention, reference will now be made to the
embodiments illustrated in the drawings and specific language will
be used to describe the same. It will nevertheless be understood
that no limitation of the scope of the invention is thereby
intended. Any alterations and further modifications in the
described embodiments, and any further applications of the
principles of the invention as described herein are contemplated as
would normally occur to one skilled in the art to which the
invention relates. One embodiment of the invention is shown in
great detail, although it will be apparent to those skilled in the
relevant art that some features that are not relevant to the
present invention may not be shown for the sake of clarity.
[0024] FIG. 1 illustrates an exemplary rifle 100 of the present
disclosure. The rifle includes in upper assembly 102 and a lower
assembly 104. The upper assembly includes an upper receiver 108, a
barrel assembly 110, a handguard assembly 112, and a bolt carrier
group 114. The lower assembly includes a lower receiver 120, and a
trigger assembly 122.
[0025] As shown in FIG. 2, the barrel assembly includes a barrel
128, a gas block assembly 130 and a gas tube 132 or a gas piston
that extends rearward from the gas block to the bolt carrier group
of the upper assembly. In direct impingement systems having a gas
tube, the rearward end of the gas tube fits inside of a gas key
mounted at the top of the bolt carrier group so that high-pressure
gas inside of the gas tube directly impinges the bolt carrier
group.
[0026] The gas block assembly includes a gas block 140 and one or
more vent plugs 190. The gas block has a first interior surface 142
defining a barrel opening 144 for the receiving the barrel. The
barrel opening extends between a rearward surface 146 and a forward
surface 148 of the gas block.
[0027] The gas block has a second interior surface 154 defining a
gas tube opening 156 for receiving the gas tube. The gas tube
opening extends forwardly from the rearward surface of the gas
block. The gas tube opening may extend only partially through the
gas block or it may extend completely through the gas block.
[0028] The gas block has a third interior surface 160 defining a
passageway 162 extending transverse to and between the barrel
opening and the gas tube opening. The passageway communicates with
a gas port 170 of the barrel so that high-pressure gas from the
barrel may travel from the gas port, into the passageway 162 and
towards the gas tube opening.
[0029] The gas block has a fourth interior surface 180 defining a
vent opening 182. The vent opening intersects the passageway 162
between the barrel opening and the gas tube opening. The vent
opening is arranged to receive a vent plug 190. For example, the
fourth interior surface may have a threaded portion for threadably
receiving the vent plug. The vent opening can extend in a forward
direction from the passageway so as to open on the forward surface
of the gas block.
[0030] The vent plug may be a removable plug. The vent plug can be
sized and arranged so as to block a portion of the vent opening.
For example, the vent plug may be arranged to fill a
cross-sectional area of the vent opening.
[0031] The vent plug can have a self-locking portion to secure the
plug to the gas block. For example, the vent plug may be formed of
a first material (e.g., metal) and include a locking, second
material (e.g., a polymeric material) to increase the frictional
resistance between the vent plug and the gas block.
[0032] FIGS. 7A to 7E illustrate embodiments of vent plugs. The
vent plug may be free of an opening extending along a length of the
vent plug, or, alternatively, the vent plug may have an internal
surface 192 defining an opening 194 that extends along a length of
the plug. For example, the vent plug may have an opening that
extends from a rearward surface 196 to a forward surface 198. The
opening can have a portion extending linearly through the vent
plug.
[0033] The opening in the vent plug in the plug is arranged to vent
high-pressure gas out of the firearm. Advantageously, such an
arrangement can reduce the gas pressure delivered through the gas
block into the gas tube and, consequently, to the action of the
firearm. Additionally, Applicant has found that venting
high-pressure gas out of the gas block can reduce carbon fouling
over time. Moreover, venting high-pressure gas out of the gas block
can reduce the risk of gas leakage at the interface between the gas
block and the barrel.
[0034] Vent plugs may have openings of different sizes and/or
shapes. For example, a vent plug may have an opening having a
hydraulic diameter that is larger than a hydraulic diameter of
another plug. Similarly, a vent plug may have an opening with a
cross-sectional shape different from another vent plug (the
cross-sectional shape being determined either in a plane orthogonal
or parallel to a longitudinal axis of the vent plug).
[0035] The vent plug can be arranged to selectively block portions
of the passageway of the gas block. As shown in FIG. 8, such an
arrangement can restrict the amount of gas that passes through the
gas block into the gas tube. For example, the plug may operate as a
valve (e.g., needle valve or ball valve) that can be operated to
increase and/or decrease the hydraulic diameter of a portion of the
passageway. FIGS. 7B and 7E illustrate embodiments wherein the vent
plug has a length sufficient to extend to the passageway in the gas
block when positioned in the vent opening. In at least such
instances, the vent plug may have a first length 210 with external
threads and a second length 212 free of external threads, with the
second length arranged to extend, at least partially, into the
passageway of the gas block.
[0036] Vent plugs may be provided in various lengths and/or with
indicia that index to the gas block. For example, vent plugs may be
provided in various lengths arranged to block predetermined amounts
(e.g., 10%, 20%, 30%, 40%, or 50%) of the passageway when the
forward end of the vent plug is flush with the forward surface of
the gas block. Alternatively, or additionally, vent plugs may have
indicia along a portion of the vent plug (e.g., along a length
thereof or radially around the vent plug) corresponding to the
extent the passageway is blocked when the marking is indexed to a
corresponding indicia or surface of the gas block. For example, a
vent plug may have a first indicia that corresponds to a tuned
configuration for a first ammunition and a second indicia that
corresponds to a tuned configuration for a second ammunition.
[0037] The vent opening may vary in cross-sectional dimension
(e.g., hydraulic diameter) along the length thereof. For example, a
first length 220 of the vent opening proximal an outer surface of
the gas block may have a larger maximum cross-sectional dimension
than a second length 222 of the vent opening adjacent the
passageway. The vent plug(s) may have a corresponding shape.
[0038] Kits containing one or more vent plugs are envisioned. For
example, kits can contain a plurality of vent plugs having
different vent plug lengths and/or openings of different sizes for
venting high-pressure gas. Additionally or alternatively, kits may
contain a vent plug without an opening and a vent plug with an
opening for venting high-pressure gas. Kits having one or more vent
plugs may include the gas block and/or the gas tube.
[0039] The gas block may include a barrel pin opening 252 defined
by a barrel pin surface 254 extends transverse to the barrel
opening. When a barrel is positioned within the barrel opening of
the gas block, a barrel pin 256 may be inserted between a pin
surface 258 of the barrel and the barrel pin surface 254 of the gas
block. Advantageously, the pin can resist rotation and/or lateral
movement of the gas block relative to the barrel so as to maintain
alignment of the passageway of the gas block with the gas port of
the barrel.
[0040] The gas block may include one or more openings to receive
setscrews for securing the gas block to the barrel. Such setscrews
may be included with any of the kits or assemblies described
herein.
[0041] Extending transverse to the gas tube opening is a gas tube
pin opening 270 for receiving a gas tube pin 272. The gas tube pin
serves to secure the gas tube in the gas tube opening with a port
280 of the gas tube aligned with the passageway of the gas
block.
[0042] Any of the above-described embodiments may be provided as a
kit or assembled on a portion of a firearm. For example, the gas
block assemblies described herein may be provided on barrels,
including barrels attached to upper receivers, or barrels of
completed firearms.
MODES OF OPERATION
[0043] Advantageously, the gas block assemblies described herein
can be operated in different modes, as may be selected by the
operator. In a first mode, the gas block may have a vent plug
blocking the vent opening without venting high-pressure gas out of
the gas block or blocking a portion of the passageway.
[0044] In a second mode, a ported vent plug (e.g., a vent plug with
an opening that allows the passage of high-pressure gas) may be
positioned in the vent opening. In the second mode, a vent plug may
be selected based on opening (e.g., orifice) size. As mentioned
above, the opening is arranged to vent high-pressure gas out of the
gas block so less pressure and/or gas volume reaches the gas tube
or gas piston.
[0045] In a third mode of operation, a vent plug having a portion
blocking a portion of the passageway is positioned in the vent
opening. The vent plug can be selectively positioned to limit the
gas pressure and/or volume that passes through the gas block and to
the gas tube or gas piston.
[0046] In a fourth mode of operation, the vent plug both blocks a
portion of the passageway and has an opening to vent high-pressure
gas out of the gas block.
Methods of Use
[0047] A method of using the gas block assembly in the second mode,
discussed above, will now be discussed with reference to FIG. 9. In
stage 902 of method 900, an operator shoots the firearm with a
ported vent plug (i.e., a vent plug with an opening) in the vent
opening. The operator then inspects, stage 904, whether the firearm
properly extracted and ejected the spent cartridge and locked the
bolt to the rear after the last shot fired (e.g., from a magazine
or clip). If the firearm failed to extract and eject the spent
cartridge and lock the bolt to the rear after the last shot fired,
then the operator replaces the vent plug with one having a smaller
opening, stage 906. The operator will repeat this process (i.e.,
shooting and inspecting whether the firearm properly extracted and
ejected the spent cartridge and locked the bolt to the rear after
the last shot). Once the firearm successfully extracts, ejects, and
locks the bolt to the rear after the last shot, the gas block is
considered tuned for that configuration (ammunition, suppressor,
etc.). To ensure proper operation, the shooter should fire several
test shots, in stage 908, to confirm proper operation. Finally, an
operator may lock the vent plug in position in the vent opening,
such as by using a setscrew and/or a thread-locking fluid in stage
910.
[0048] In tuning the second mode, it is preferable that the
operator start with a vent plug having a large opening and then
work progressively to vent plugs with smaller openings. However, it
is envisioned that an operator may start with a vent plug with a
small opening (or no opening) and then move to vent plugs with
larger openings, as shown in method 1000 of FIG. 10. In this
"reverse" procedure, an operator shoots the firearm with a vent
plug in the vent opening, in stage 1002. The operator then
inspects, stage 1004, whether the firearm properly extracted and
ejected the spent cartridge and locked the bolt to the rear after
the last shot fired (e.g., from a magazine or clip). If the firearm
properly extracted and ejected the spent cartridge and locked the
bolt to the rear, the operator may replace the vent plug with one
having a larger opening, stage 1006, and repeat the process to
determine whether the firearm functions properly with the
larger-opening vent plug. The operator will repeat this process
(i.e., shooting and inspecting whether the firearm properly
extracted and ejected the spent cartridge and locked the bolt to
the rear after the last shot). Once the firearm fails to
successfully extract, eject, and lock the bolt to the rear after
the last shot, the vent opening will be considered too large. The
operator will then replace the vent plug with one having a smaller
opening, stage 1008, and fire one or more additional test shots to
ensure proper operation of the firearm in stage 1010. Finally, an
operator may lock the vent plug in position in the vent opening,
such as by using a setscrew and/or a thread-locking fluid in stage
1012.
[0049] In a method 1100 of tuning the third mode, the operator
shoots the firearm with the vent plug positioned in the vent
opening and at least partially blocking the vent passageway (i.e.,
stage 1102). The shooter then inspects whether the firearm properly
extracted and ejected the spent cartridge and locked the bolt to
the rear after the last shot fired (e.g., from a magazine or clip)
in stage 1104. If the firearm failed to extract and eject the spent
cartridge and lock the bolt to the rear after the last shot fired,
then the operator backs the vent plug out (i.e., out of the
passageway) slightly (e.g., 1/4 turn or 1/2 turn) in stage 1106 and
repeats the process. Once the firearm properly extracts and ejects
the spent cartridge and locks the bolt to the rear, the operator
may unscrew the vent plug an additional amount (e.g., an additional
1/4 turn) in stage 1108 to accommodate for minor variability (e.g.,
temperature, air pressure, etc.). If desired, the operator may lock
the vent plug in position in the vent opening, such as by using a
setscrew and/or a thread-locking fluid in stage 1110.
[0050] The method of tuning the third mode may also be performed in
reverse (i.e., gradually increasing the amount the vent plug blocks
the passageway) until the firearm ceases to function properly. The
vent plug may then be backed out a desired amount and the firearm
tested to confirm proper operation. As with the other methods
disclosed, once proper operation of the firearm is achieved, the
operator may lock the vent plug in position in the vent opening,
such as by using a setscrew and/or a thread-locking fluid.
[0051] The above methods can be performed before, during, and/or
after changes to the firearm's configuration. For example, one or
more of the above methods may be performed on the firearm before
and/or after a suppressor has been attached to the end of the
barrel.
[0052] When switching between different firearm configurations
(e.g., ammunition types, brands, or "loads", suppressed or not
suppressed, etc.), an operator may simply swap the vent plug in the
gas block with one tuned for that configuration. For example, when
switching from shooting the firearm without a suppressor to
shooting the firearm with a suppressor, an operator may replace the
vent plug with one having a larger opening. Similarly, an operator
switching between different types of ammunition (e.g., high-power
ammunition to subsonic) may simply replace the vent plug with one
tuned for the new ammunition.
[0053] Once an operator has found a vent plug configuration (e.g.,
vent plug length, opening size and/or positioning in the gas block)
for a particular firearm configuration, an operator will be able to
quickly switch between those firearm configurations and "re-tune"
the gas block without having to repeat the experimental process
initially used to identify the appropriate vent plug. The operator
may record the vent plug(s) and/or vent plug positioning in the
vent opening for a particular firearm configuration so that the gas
block assembly can be configured for that configuration without
further experimentation.
[0054] The following numbered clauses set out specific embodiments
that may be useful in understanding the present invention:
[0055] 1. A method of tuning an adjustable gas block assembly of a
firearm, comprising: firing a cartridge in the firearm with the gas
block assembly having a first vent plug positioned within a vent
opening;
[0056] determining whether the firearm properly extracted and
ejected the cartridge and chambered a new cartridge or locked a
bolt of the firearm in an open configuration;
[0057] replacing the first vent plug of the gas block assembly, the
first vent plug having an opening extending along a length thereof,
with a second vent plug having an opening extending along a length
thereof, wherein the opening of the first vent plug has a different
hydraulic diameter than the opening of the second vent plug;
and
[0058] firing a cartridge in the firearm with the gas block
assembly having the second vent plug positioned within the vent
opening.
[0059] 2. The method of clause 1, wherein the opening of the second
vent plug has a smaller hydraulic diameter than the opening of the
first vent plug.
[0060] 3. The method of clause 1, wherein the opening of the second
vent plug has a larger hydraulic diameter than the opening of the
first vent plug.
[0061] 4. A gas block assembly for a firearm, comprising:
[0062] a gas block defining a barrel opening, a gas tube opening, a
passageway extending from the barrel opening to the gas tube
opening, and a vent opening intersecting the passageway; and
[0063] a vent plug received within the vent opening;
[0064] wherein the vent plug has an opening extending along a
length of the vent plug and in communication with the passageway so
that high-pressure gas communicating with the passageway can pass
through the opening in the vent plug and out of the gas block
assembly.
[0065] 5. The gas block assembly of clause 4, wherein the vent plug
is removably received within the vent opening.
[0066] 6. The gas block assembly of clause 4 or 5, wherein the vent
plug is threadably received within the vent opening.
[0067] 7. The gas block assembly of any one of clauses 4-6, wherein
the vent opening is positioned between the gas tube opening and the
barrel opening.
[0068] 8. The gas block assembly of any one of clauses 4-7, wherein
the vent opening extends from a forward surface of the gas block
rearward to the passageway and wherein the gas tube opening extends
from a rearward surface of the gas block forwardly to the
passageway.
[0069] 9. The gas block assembly of any one of clauses 4-8, wherein
the vent plug has a length sufficient to extend at least partially
into the passageway when received within the vent opening.
[0070] 10. The gas block assembly of any one of clauses 4-9,
wherein the vent opening has a first cross-sectional dimension
adjacent an outer surface of the gas block and a second
cross-sectional dimension adjacent the passageway and intermediate
the passageway and the first cross-sectional dimension; and
[0071] wherein the second cross-sectional dimension is smaller than
the first cross-sectional dimension.
[0072] 11. The gas block assembly of clause 9, wherein the vent
plug has a first end matching the first cross-sectional dimension
and a second end matching the second cross-sectional dimension.
[0073] 12. The gas block assembly of clause 10 or 11, wherein the
first cross-sectional dimension portion of the vent opening is a
threaded portion and the second cross-sectional dimension portion
is free of threads.
[0074] 13. An upper assembly for a firearm, comprising:
[0075] the gas block assembly of any one of the preceding
clauses;
[0076] an upper receiver; and
[0077] a barrel attached to the upper receiver;
[0078] wherein the gas block assembly is attached to the
barrel.
[0079] 14. A firearm, comprising:
[0080] the upper assembly of clause 13 attached to a lower
assembly.
[0081] 15. A kit, comprising:
[0082] a first vent plug for a gas block and a second vent plug for
the gas block;
[0083] wherein the first and second vent plugs each have a length
and at least one of the first and second vent plugs has an orifice
extending through the length thereof.
[0084] 16. The kit of clause 15, wherein:
[0085] the first vent plug has an orifice extending through the
length thereof, the orifice having a minimum cross-sectional
dimension; and
[0086] the second vent plug has an orifice extending through the
length thereof, the orifice of the second vent plug having a
minimum cross-sectional dimension less than that of the orifice of
the first vent plug.
[0087] 17. The kit of clause 15, wherein:
[0088] the first vent plug has an orifice extending through the
length thereof and the second vent plug is free of an orifice
extending through the length thereof.
[0089] 18. The kit of any one of clauses 15-17, wherein:
[0090] the length of one of the first or second vent plugs is
greater than the other
[0091] 19. The kit of clause 18 as dependent from clause 15 or
clause 17, wherein:
[0092] the longer vent plug is free of an orifice.
[0093] 20. The kit of any one of clauses 14-19, comprising:
[0094] a gas block having a vent opening arranged to receive at
least one of the first and second vent plugs.
[0095] While the invention has been illustrated and described in
detail in the drawings and foregoing description, the same is to be
considered as illustrative and not restrictive in character, it
being understood that only the preferred embodiment has been shown
and described and that all changes, equivalents, and modifications
that come within the spirit of the inventions defined by following
claims are desired to be protected. All publications, patents, and
patent applications cited in this specification are herein
incorporated by reference as if each individual publication,
patent, or patent application were specifically and individually
indicated to be incorporated by reference and set forth in its
entirety herein.
* * * * *