U.S. patent application number 12/806623 was filed with the patent office on 2012-06-21 for assembly and noise suppressor for firearms.
Invention is credited to George Koumbis.
Application Number | 20120152093 12/806623 |
Document ID | / |
Family ID | 46232648 |
Filed Date | 2012-06-21 |
United States Patent
Application |
20120152093 |
Kind Code |
A1 |
Koumbis; George |
June 21, 2012 |
Assembly and noise suppressor for firearms
Abstract
An assembly for a firearm (10) includes a sleeve (22) connected
to the receiver or receiver end of the barrel (18). The sleeve (22)
extends beyond the discharge end of the barrel (18) and includes
inwardly extending projections (42) abutting or juxtaposed to a
peripheral section (44) of the discharge end of the barrel (18). A
noise suppressor (24, 50) threads onto the sleeve (22). Some of the
propellant gases are redirected and cooled by the noise suppressor
(24, 50) in a conventional manner. Some of the propellant gases are
redirected into an annulus (46) between the barrel (18) and sleeve
(22) where they are cooled and some of their volume is reduced
thereby increasing the efficiency of the noise suppressor (24,
50).
Inventors: |
Koumbis; George; (Portland,
TX) |
Family ID: |
46232648 |
Appl. No.: |
12/806623 |
Filed: |
October 12, 2010 |
Current U.S.
Class: |
89/14.4 ;
181/223 |
Current CPC
Class: |
F41A 21/30 20130101 |
Class at
Publication: |
89/14.4 ;
181/223 |
International
Class: |
F41A 21/30 20060101
F41A021/30 |
Claims
1. A firearm comprising a receiver having a barrel terminating in a
muzzle, the barrel being imperforate on its periphery from the
receiver to the muzzle and an assembly comprising an imperforate
rigid sleeve connected to the firearm at a location adjacent a
junction of the barrel and receiver and distant from the muzzle,
the sleeve surrounding the barrel and extending from the junction
to adjacent the muzzle; and a noise suppressor rigid with the
sleeve having a series of noise suppressing elements, an upstream
element being spaced from the muzzle, there being an annular space
between the rigid sleeve and the barrel open to receive propellant
gases exiting out of the muzzle.
2. The firearm of claim 1 wherein the sleeve is a one piece unit
and the noise suppressor comprises exactly three separate pieces
including an external tubular housing, a removable end cap
connected to the tubular housing and having a protrusion extending
outwardly beyond an end of the tubular housing and a unitary noise
suppressing section including a series of separately made noise
suppressing elements fused together to provide a series of gas
expansion chambers, the end cap being arranged to couple and
uncouple from the housing upon manipulation of the protrusion
whereby the end cap may be removed by grasping the same and
uncoupling the end cap from the tubular housing to thereby readily
disassemble the noise suppressor for cleaning.
3. The firearm of claim 1 wherein the sleeve is a one piece unit
and the noise suppressor comprises exactly two pieces including the
tubular housing and one piece comprising an end cap and a unitary
noise suppressing section comprising a plurality of separately made
noise suppressing elements fused together to provide a series of
gas expansion chambers, the end cap having a protrusion extending
outwardly beyond an end of the tubular housing, the end cap being
arranged to couple and uncouple from the housing upon manipulation
of the protrusion whereby the end cap may be grasped to uncouple
the end cap from the tubular housing to thereby readily disassemble
the noise suppressor for cleaning.
4. The firearm of claim 3 wherein the tubular housing comprises a
first connector adjacent an inlet end of the noise suppressor for
connection to the sleeve and a second connector adjacent an inlet
end of the noise suppressor for connection to the end cap/noise
suppressing section.
5. The firearm of claim 3 wherein the first and second connectors
are threads.
6. The firearm of claim 1 wherein the sleeve comprises an elongate
section made of a material selected from the group consisting of
carbon fiber, stainless steel, carbon steel, titanium alloys,
ceramics, ceramic composites and aluminum alloys.
7. The firearm of claim 1 wherein the noise suppressor comprises a
tubular housing having an imperforate side wall and providing an
entrance end and an exit end and a connector adjacent the entrance
end for attachment to a firearm; a multiplicity of separately made
noise suppressing elements, inside the housing, each of the noise
suppressing elements comprising a baffle having a central opening
for passing a projectile from the firearm, the elements being fused
together into a unit; and a closure seating against the exit end of
the housing and having a protrusion extending outwardly beyond an
end of the tubular housing, the end cap being arranged to couple
and uncouple from the housing upon manipulation of the protrusion
whereby the end cap may be grasped to uncouple the end cap from the
tubular housing to thereby disassemble the noise suppressor for
cleaning.
8. The firearm of claim 7 wherein the connector comprises a first
set of threads, wherein the housing comprises a second set of
threads adjacent the housing exit end, and wherein the closure
being a separate component from the noise suppressor element unit,
the closure abutting the exit end of the housing and having a third
set of threads mating with the second set of threads.
9. The firearm of claim 7 wherein the connector comprises a first
set of threads, wherein the housing comprises a second set of
threads on an interior of the housing adjacent the entrance end and
the noise suppressor element unit comprises a third set of threads
mating with the second set of threads on the entrance end of the
housing, the closure being of one piece with the baffle unit and
abutting the exit end of the housing.
10. The firearm of claim 7 wherein the closure is fused to the
noise suppressor unit.
11. The firearm of claim 1 wherein the sleeve extends beyond the
muzzle.
12. The firearm of claim 1 wherein the sleeve provides an internal
abutment rigid with the sleeve abutting a peripheral section of the
barrel adjacent the muzzle.
13. The firearm of claim 1 wherein the noise suppressor being
wholly supported by the sleeve.
14. A noise suppressor for a firearm comprising a tubular housing
having an imperforate side wall and providing an entrance end and
an exit end and a connector adjacent the entrance end for
attachment to a firearm; a multiplicity of noise suppressing
elements, inside the housing, each of the noise suppressing
elements comprising a baffle having a central opening for passing a
projectile from the firearm, the elements being separately made and
then fused together into a unit; and a closure seating against the
housing and having a protrusion extending outwardly from an end of
the tubular housing sufficiently far for a user to grasp, the
closure being arranged to couple and uncouple from the housing upon
manipulation of the protrusion; the noise suppressor comprising no
more than three parts whereby it may be readily disassembled, for
cleaning, by manipulating the protrusion.
15. The noise suppressor of claim 14 wherein the connector
comprises threads.
16. The noise suppressor of claim 14 wherein the connector is
adjacent the housing entrance end, wherein the housing comprises a
second connector adjacent the housing exit end, and wherein the
closure being a separate component from the noise suppressor
element unit, the closure abutting the exit end of the housing and
having a third connector mating with the second connector.
17. The noise suppressor of claim 14 wherein the connector is
adjacent the housing entrance end, wherein the housing comprises a
second connector on an interior of the housing adjacent the
entrance end and the noise suppressor element unit comprises a
third connector mating with the second connector on the entrance
end of the housing, the closure being of one piece with the baffle
unit and abutting the exit end of the housing.
18. The noise suppressor of claim 14 wherein the noise suppressing
elements are welded together.
19. The noise suppressor of claim 14 wherein the closure is fused
to the suppressing unit and the noise suppressor comprises exactly
two separate pieces.
20. The noise suppressor of claim 14 wherein the noise suppressor
comprises exactly three separate pieces.
21. The noise suppressor of claim 14 comprising a structure located
at the entrance end of the housing that is concave away from the
exit end of the housing for deflecting some propellant gases out of
the entrance end of the housing.
Description
[0001] This application is based on Provisional Patent Application
Ser. No. 61/066,705, filed Feb. 21, 2008 on which priority is
claimed and PCT/US2009/001062 filed Feb. 19, 2009.
[0002] This invention relates to an assembly and noise suppressor
for rifles, automatic weapons, pistols, shotguns and similar
firearms.
BACKGROUND OF THE INVENTION
[0003] Conventional silencers or noise suppressors are devices
attached to the barrel of rifles, pistols and similar firearms for
reducing the noise attendant upon firing of ammunition. Silencers
are typically attached by machining threads on the discharge end of
the barrel and then threading the silencer onto the barrel. This
has a number of disadvantages, most particularly in high accuracy
rifles, because the weight of the silencer deflects the barrel
enough to affect the point of impact of rounds fired through the
barrel. Given the strength of rifle barrels, this may sound
implausible but is an awkward fact. Sniper rifles are equipped with
scopes that have two settings, one for use with a silencer and one
without. In the alternative, a second scope is used to counter the
effect of barrel distortion caused by the weight of the
silencer.
[0004] U.S. Pat. Nos. 832,695; 1,111,202; 1,140,578; 1,401,667;
4,341,283; 4,588,043; 4,920,854; 5,029,512; 5,164,535; 5,679,916;
5,753,846; 6,374,718; 6,575,074; 7,237,467 and 7,308,967 disclose
various types of noise suppressor and/or silencer assemblies for
firearms.
SUMMARY OF THE INVENTION
[0005] In this invention, an assembly is attached to the receiver
of the rifle or to the barrel adjacent the junction of the barrel
and receiver so the assembly is supported independently of the end
of the barrel from which the projectile emerges. This is
accomplished by securing a rigid load bearing support, which acts
as a heat shield or stabilizer tube, to the receiver or to the
barrel adjacent its junction with the receiver and attaching a
noise suppressor to the support. Thus, the weight of the noise
suppressor is not supported on the discharge end of the barrel so
the accuracy of the firearm is not adversely affected by the weight
of the suppressor. The support comprises an imperforate sleeve
connected to the receiver or to the receiver end of the barrel. In
most embodiments, the sleeve is threaded onto the receiver. The
sleeve extends somewhat past the discharge end of the barrel. A
noise suppressor is fixed to the distal end of the sleeve and
provides a passage aligned with the barrel passage so fired
projectiles pass seamlessly through the noise suppressor. The noise
suppressor is preferably threaded onto the sleeve end.
[0006] This approach has many advantages. First, the weight of the
noise suppressor is transmitted by the sleeve to the receiver
independently of the barrel so the weight of the noise suppressor
does not distort the barrel nor affect the point of impact of
projectiles. Second, the annulus between the barrel exterior and
the sleeve interior provides an expansion chamber for cooling
propellant gases thereby enhancing the silencing ability of the
device. Third, because the sleeve and noise suppressor are readily
removable from the receiver, the device is easy to clean without
sophisticated cleaning equipment. Fourth, projections on the inside
of the sleeve abut the barrel near its discharge end damp barrel
harmonic vibrations thereby promoting smaller impact groups.
[0007] In some embodiments, a novel noise suppressor is made in
either two or three parts so it can be easily detached from the
weapon, disassembled and cleaned without contending with many
individual components. Although the noise suppressor is ideally
suited for use with the sleeve surrounding the barrel as described
above, it may be threaded or provided with an adapter to attach
directly to the discharge end of a barrel in a conventional
manner.
[0008] It is an object of this invention to provide an improved
assembly for a firearm.
[0009] A further object of this invention is to provide an assembly
including a noise suppressor which is supported from the receiver
or barrel end adjacent the receiver, independently of the discharge
end of the barrel.
[0010] These and other objects and advantages of this invention
will become more apparent as this description proceeds, reference
being made to the accompanying drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a side view of a conventional rifle which has been
modified to receive an assembly of this invention;
[0012] FIG. 2 is a side view of a sleeve or tubular beam that is
attached to the rifle of FIG. 1;
[0013] FIG. 3 is a side view of a noise suppressor attached to the
end of the sleeve of FIG. 2;
[0014] FIG. 4 is a partial isometric view of the receiver end of a
barrel modified in accordance with this invention;
[0015] FIG. 5 is an isometric view of a barrel ring attachment of
this invention;
[0016] FIG. 6 is a broken isometric view of the receiver end of a
sleeve or tubular beam providing, at its opposite end, an
attachment for a noise suppressor;
[0017] FIG. 7 is a broken isometric view of the barrel end of the
sleeve or tubular beam of FIG. 2;
[0018] FIG. 8 is an exploded isometric view of one embodiment of a
noise suppressor;
[0019] FIG. 9 is an exploded cross-sectional view of the noise
suppressing unit of the suppressor of FIG. 8, the noise suppressing
elements being shown in non-rotated positions and the tubular
housing being omitted for purposes of illustration;
[0020] FIG. 10 is an exploded cross-sectional view of the barrel
discharge end, end of the tubular beam of FIGS. 3 and 5 and a noise
suppressor;
[0021] FIG. 11 is an isometric view of the entrance end of the
noise suppressor of FIGS. 8 and 9;
[0022] FIG. 12 is an exploded isometric view of another embodiment
of a noise suppressor;
[0023] FIG. 13 is a view, similar to FIG. 9, of the noise
suppressor of FIG. 12 illustrating the noise suppressing elements
in non-rotated positions and eliminating the tubular housing for
purposes of illustration;
[0024] FIG. 14 is a side view of the rifle of FIG. 1 with a tubular
beam secured to the receiver around the outside of the barrel and a
noise suppressor on the end of the tubular beam;
[0025] FIG. 15 is a side view of another conventional firearm
equipped with a conventional muzzle brake or flash suppressor;
and
[0026] FIG. 16 illustrates the firearm of FIG. 15 equipped with an
assembly of this invention.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Referring to FIGS. 1-11, a rifle 10 is illustrated as of a
bolt action type having a stock 12, a bolt 14, a receiver 16 and a
barrel 18. Those skilled in the art will recognize the rifle 10 as
being a conventional rifle known as a Fabrique National (FN) of the
free floating barrel type where the barrel is attached to the
receiver 16 but is slightly movable relative to the stock 12. Those
skilled in the art will recognize that free floating barrel type
rifles comprise the majority of modern "counter sniper" weapons, as
well as for all versions of the M16 and its civilian version, the
AR15.
[0028] As shown by a comparison of FIGS. 1 and 14, the rifle 10 has
been modified by incorporating an assembly 20 which includes a
rigid imperforate sleeve or tubular beam 22 and a noise suppressor
24. The sleeve 22 is fixed to the receiver 16 or to the barrel 18
adjacent its junction with the receiver 16 in any suitable manner,
as by welding, mating threads, adhesives or the like. Preferably,
the sleeve 22 is threaded onto the rifle 10 as explained more fully
hereinafter. It will be seen that the sleeve 22 is independent of
the barrel 18 or is, at least, independent of the discharge end of
the barrel 18. In preferred embodiments, the sleeve 22 is threaded
onto the rifle 10 as shown best in FIG. 4 where the receiver 16 or
the receiver end of the barrel 18 is machined to provide threads 26
for receiving one end of the tubular beam 22. In order to provide a
clean appearance when the assembly 20 is removed from the rifle 10,
a barrel ring protector 28 shown in FIG. 5 may be threaded onto the
receiver 16 to hide the threads 26.
[0029] The tubular beam 22, as shown best in FIGS. 6-7, includes an
imperforate elongate section 30 which, in the illustrated
embodiment, is a composite material made of fibers and a resin,
such as a carbon fiber composite having characteristic high
strength, low weight, high heat tolerance, extreme heat
dissipation, high corrosion resistance and high heat insulating
qualities. The carbon fiber composite material is made in any
suitable manner and the components are commercially available. In
some embodiments, a barrel ring attachment 32 is fixed in a
proximal end of the beam 22 in any suitable manner, as by
threading, adhesives, welding or the like.
[0030] In the alternative, the elongate section 28 may be made of
carbon steel, stainless steel, aluminum alloy, titanium alloy,
ceramics, ceramic composites or any other suitable metal or alloy
depending on the requirements of the particular task at hand. In
these embodiments, the threaded end of the sleeve 22 can be
provided simply by threading the end of the sleeve.
[0031] In some embodiments, the attachment 32 is metal such as
stainless steel, carbon steel, titanium alloys, aluminum alloys or
the like. The attachment 32 includes female threads 34 sized to
pass onto the external threads 26 on the sleeve 20 thereby securing
the sleeve 20 to the receiver 16 of the rifle 10 or to the barrel
end adjacent the receiver 16. It will be seen that the sleeve 20
connects to the firearm 10 independently of the discharge end of
the barrel 18 so that supporting the noise suppressor 24 on the
sleeve 20 does not distort the barrel 18.
[0032] The distal or discharge end of the tubular beam 22 receives
a barrel aligner 36 which is secured in the inside of the tubular
section 30 in any suitable manner, as by welding, threading,
adhesives or the like. In some embodiments, the barrel aligner 36
includes a metal body 38 such as stainless steel, carbon steel,
titanium alloys, aluminum alloys, ceramics, ceramic composites or
the like. The body 38 includes interior threads 40 for receiving
threads of the noise suppressor 24 and a series of rigid inwardly
directed projections or shoulders 42 which may be generally
perpendicular to the barrel 18. The inner ends of the projections
42 are spaced to slip over and abut a peripheral section 44 of the
discharge end of the barrel 18. It will be seen that the
projections 42 prevent the sleeve 22 from being installed backwards
on the barrel 18 because they will interfere with a larger part of
the barrel 18 near the receiver 16 so the threads 34 cannot engage
the threads 26.
[0033] As shown best in FIG. 10, the noise suppressor 24 and sleeve
20 are arranged to allow propellant gases to flow into an annulus
46 between the interior of the sleeve 20 and the exterior of the
barrel 18. This may be accomplished in a variety of ways, as by
threading the noise suppressor 24 into the barrel aligner 36 so the
threads bottom out before the noise suppressor 24 abuts the end 48
of the barrel 18. The distance the noise suppressor 24 is spaced
from the barrel end 48 is subject to considerable variation but
need not be overly extensive because the volume of the annulus 46
is normally very large compared to the volume between the barrel
end 48 and the noise suppressor 24. This allows the noise
suppressor 24 to be shorter than conventional suppressors which are
typically spaced several inches from the barrel end. In most
embodiments, this distance may be on the order of an inch or
so.
[0034] In prototypes of the sleeve 20, the elongate section 30 is a
carbon fiber tube while the barrel ring attachment 32 and barrel
aligner 36 are carbon steel which has been treated to be black. In
the prototype, the inside of the barrel aligner 36 has to be
closely inspected to see that the projections 42 do not come
directly out of the carbon fiber tube 30.
[0035] The noise suppressor 24 shown in FIG. 8 is of an unusual or
unconventional design comprising only three separate pieces, i.e. a
tube or housing 50, a noise suppressing unit 52 closely received
inside the housing 50 and a closure or end cap 54. Although the
noise suppressor 24 may be made of any suitable material compatible
with the rifle 10, in some embodiments, the housing 50 can be made
of carbon fiber composite having a metal fitting 56 fixed on the
entrance end of the noise suppressor 24 providing an opening 57 for
passing a projectile, threads 58 for attachment to the barrel
aligner 36 and threads 59 for attachment to the tubular housing 50.
The entrance end of the housing 50 includes a structure or groove
61 which is concave toward the muzzle end of the barrel 18 for more
efficiently deflecting or directing propellant gases toward the
annulus 46 provided by the sleeve 22 and barrel 18. It will be seen
that the groove 61 is concave in a direction away from the exit end
of the housing 50.
[0036] The noise suppressing unit 52 comprises a series of
more-or-less identical noise suppressing segments 60 which are
fused together, either by welding after machining, by machining a
single billet or by casting the segments 60 as a single unit. The
noise suppressing segments 60 are shown best in FIG. 9 and include
a frustoconical baffle 62 providing an axial opening 64 therein of
a size to pass a projectile from the barrel 18. The frustoconical
baffle 62 has a small diameter end facing the barrel end 48 and a
pair of laterally or radially facing openings 66 communicating
between an interior volume 68 and grooves 70 extending around the
segment 60 as shown best in FIG. 8.
[0037] It will be seen that propellant gases passing into the
suppressor 24 are deflected by the frustoconical baffles 62. At the
entrance end of the suppressor 24, some of the propellant gases are
deflected into the annulus 46 between the sleeve 22 and the barrel
18. Because the annulus 46 is relatively large, the silencing
efficiency of the assembly 20 is much increased compared to a
conventional noise suppressor. It will be apparent that this
invention incorporates a very large gas expansion chamber for a
noise suppressor while adding only a very small increment of length
to the rifle 10 as best seen in a comparison of FIG. 1 with FIG.
14.
[0038] Each succeeding baffle 62 deflects some of the propellant
gas through the lateral openings 66 of the upstream segment 60. In
some embodiments, as shown in FIG. 8, the segments 66 are
progressively offset relative to the upstream segment in order to
slightly direct the gas in a rotating manner around the axis of the
suppressor unit 52. The more gas movement created inside the
suppressor 24, the more the gas is cooled. In addition, some of the
gas gets trapped in the grooves 70 to the same effect. Although the
amount of angular offset may vary widely, a preferred amount of
offset is in the range of 30-45.degree. for more efficiently
rotating propellant gas around the suppressor unit 52.
[0039] The end cap 54 is conveniently made of metal having an
opening 71 aligned with the openings 57, 64 and threads 72 for
attachment to threads 74 machined in the exit end of the tube 50.
It will be seen that the suppressor 24 comprises only three pieces
so it may be disassembled simply by unscrewing it from the rifle
10, unscrewing the end cap 54 and allowing the noise suppressing
unit 52 to fall out of the tube 50. These components can be rinsed
off and reassembled as quickly. Because the interior of noise
suppressors inherently accumulate propellant debris, the ability to
quickly disassemble, clean and reassemble the suppressor 24 is a
major advantage. In a combat situation where sand, grit, mud and
the like will accumulate in the suppressor 24, this advantage is
particularly important.
[0040] Assembly of the assembly 20 of this invention should now be
apparent. Conveniently, the sleeve 22 is first threaded onto the
barrel 18 so the projections 42 slip over the peripheral end 44 of
the barrel 18. At this stage of assembly, the tubular beam 20
becomes a heat shield and can stay on a rifle as such without
installation of the noise suppressor 24 and thus without altering
the noise of the rifle.
[0041] When the suppressor 24 is threaded into the barrel aligner
36, the bores 57, 64, 71 of the noise suppressor 24 align with the
barrel bore 76. It will be seen that the weight of the noise
suppressor 24 is borne by the tubular beam 22 independently of the
discharge end of the barrel 18. In conventional noise suppressors,
there is one point of alignment between the barrel bore and the
suppressor, which are the threads between them. In the assembly 20,
there are three points of alignment, i.e. the connection between
the sleeve 22 and the barrel 18, the projections 42 abutting the
muzzle end of the barrel 18 and the connection between the barrel
aligner 36 and the noise suppressor 24. This inherently is a more
reliable technique of sending projectiles down the center of the
noise suppressor 24.
[0042] It is said that the only perfect noise suppressor is one
that captures all of the gases generated by powder burning in the
fired cartridge. In this invention, the propellant gases are
partially trapped in chambers between the baffles 62 and a sizeable
portion of the gases are redirected rearwardly into the annulus 46
or into the annulus between the side walls 70 and the housing 50.
These redirected propellant gases cool off and thereby drastically
reduce in volume thereby reducing the sound producing ability of
the gases. Shortly after the projectile clears the suppressor 24,
the redirected propellant gases leak off through the suppressor 24
in a conventional manner so the pressure generated in the annulus
ultimately dissipates. By supporting the noise suppressor 24 from
the receiver 16 or from the back of the barrel 18 at a location
near its junction with the receiver 16, the weight of the noise
suppressor 24 cannot distort the barrel 18 and therefore cannot
affect the point of impact of projectiles fired from the rifle
10.
[0043] It will be seen that it is easy to clean the sleeve 22.
After removing the noise suppressor 24, the sleeve 22 can be
unthreaded from the receiver 16. The inside of the sleeve 22 can
accordingly be cleaned in any suitable manner.
[0044] Referring to FIGS. 15-16, a conventional rifle 78 which will
be recognized by those skilled in the art as an M16 is modified by
installing an installation sleeve 80 having threads to receive a
sleeve 82. A noise suppressor 84 is threaded onto the end of the
sleeve 82. It will be seen that the sleeve 82 slips over the
existing flash suppressor/muzzle brake rather than having to remove
it as with conventional noise suppressors. In addition, an existing
flash suppressor or muzzle brake directs gas laterally before it
reaches the suppressor 84 thereby making the suppressor 84 more
effective. FIG. 16 shows that the suppressor 84 need not be the
same diameter as the sleeve 82. It will be apparent that a sleeve
and noise suppressor of this invention may be attached to firearms
of almost any description.
[0045] A test firing was conducted on Sep. 22, 2008 at a location
near Corpus Christi, Texas at an outdoor shooting range. The
temperature was 85.degree. F. on a sunny day with low humidity and
no wind. A Savage Arms Model 10FP, caliber 7.62 NATO (.308
Winchester) was fired by an experienced marksman and the trial was
coordinated by a Production Manager experienced in quality control.
The rifle was equipped with a Harris bipod placed on a steel table
with the shooter being seated. The target was downrange 200 yards
from the shooter. The target was pressed wood backed paper with
cross centers at 200 yards. The ammunition was Federal Premium,
Gold Medal Match, 168 grain Sierra Matchking, BTHP. The scope was a
Leopold MKIV, Police Tactical. Ten groups of five rounds each were
fired without the assembly 20 of this invention and ten groups of
five rounds each were fired with the assembly 20 of this invention.
The rifle was not rezeroed nor was the scope setting adjusted after
firing rounds without the assembly 20. The average group size
without the assembly 20 was 1.25 inches in diameter. The average
group size with the assembly 20 was 1.15 inches in diameter. The
sound level unsuppressed was 162 decibels. The sound level
suppressed was 96 decibels for a 66 decibel reduction. One thing is
very clear: the assembly 20 did not deleteriously affect the
accuracy of the rifle. The improvement in group size is necessarily
small and it is difficult to conclude, given the small sample size,
that this will always hold true. But, it suggests that the
projections 42 are effective to dampen harmonic vibrations of the
rifle barrel and thereby improve accuracy when compared to the same
unsuppressed rifle.
[0046] Referring to FIG. 12, another embodiment of a noise
suppressor 86 is illustrated. The noise suppressor 86 has exactly
two separate pieces, i.e. a housing 88 and a combined noise
suppressing and closure unit 90. The housing 88 may be
substantially identical to the housing 50 except the fitting 92
includes one set of external threads 94 for attachment to the
barrel aligner 36 and a second set of internal threads 96 for
receiving the threads 98 of the unit 90. The unit 90 also includes
a series of noise suppressing segments 100 fused together and an
end cap 102 abutting the end of the housing 88. The noise
suppressor 86 has several advantages over the suppressor 24. First,
the inside of the housing 88 need not be machined to provide
threads to receive the end cap. Second, there are only two separate
pieces so cleaning of the suppressor 86 is even easier and losing
one of the parts is even less remote. Third, the suppressing unit
90 cannot be installed backwards.
[0047] After seeing the noise suppressor 86, it will be apparent
that the noise suppressor 24 may be modified by fusing the end cap
54 to the suppressing unit 52 and thereby reducing the number of
separate pieces to exactly two. This also has the advantage of
preventing misassembly of the noise suppressor 24.
[0048] Although the noise suppressors 24, 86 are of unusual design,
a more conventional noise suppressor can readily be adapted for use
in this invention by attachment to the barrel aligner 36 with a
suitable adapter coupling. It will also be apparent that the
suppressors 24, 86 can be manufactured to thread directly onto the
end of a conventionally threaded barrel or a suitable adapter may
be provided to thread onto a barrel and receive the threads 56,
92.
[0049] Although threads are illustrated as connecting the sleeve
and rifle and connecting the noise suppressor and sleeve, it will
be understood that other suitable connectors may likewise be used,
such as interlocking lugs or the like.
[0050] Although this invention has been disclosed and described in
its preferred forms with a certain degree of particularity, it is
understood that the present disclosure of the preferred forms is
only by, way of example and that numerous changes in the details of
operation and in the combination and arrangement of parts may be
resorted to without departing from the spirit and scope of the
invention as hereinafter claimed.
* * * * *