U.S. patent number 3,732,776 [Application Number 05/181,486] was granted by the patent office on 1973-05-15 for blank firing attachment.
This patent grant is currently assigned to The United States of America as represented by the Secretary of the Army. Invention is credited to Robert E. Snodgrass.
United States Patent |
3,732,776 |
Snodgrass |
May 15, 1973 |
BLANK FIRING ATTACHMENT
Abstract
A blank firing attachment is provided for automatic weapons
which comprises cylindrical member one end of which is open for
slideable mounting on the muzzle end of the weapon barrel. A collet
and split ring arrangement is associated with the open end of the
member and is adjustable with respect thereto to hold the
attachment on the muzzle end and effect substantial sealing
engagement therewith whereby the expanding gases incident to firing
blank ammunition are confined within the barrel for accomplishing
automatic operation in a manner well-known in the art. The housing
is also provided with vent means for controlled release of the
gases within the barrel.
Inventors: |
Snodgrass; Robert E.
(Davenport, IA) |
Assignee: |
The United States of America as
represented by the Secretary of the Army (Washington,
DC)
|
Family
ID: |
22664471 |
Appl.
No.: |
05/181,486 |
Filed: |
September 17, 1971 |
Current U.S.
Class: |
89/14.5 |
Current CPC
Class: |
F41A
21/26 (20130101) |
Current International
Class: |
F41A
21/00 (20060101); F41A 21/26 (20060101); F41f
017/00 () |
Field of
Search: |
;89/14R,14A,14B,14C,14D,14E,14SB ;42/79 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Borchelt; Benjamin A.
Assistant Examiner: Tudor; Harold
Claims
I claim:
1. A blank firing attachment for a rifle barrel the muzzle end of
which is provided with annular shoulder means, said attachment
comprising a cylindrical housing having one end thereof open and
dimensioned to slideably fit over said shoulder means, split
sealing ring means disposed for engagement with the side of said
shoulder means remote from the muzzle end of said barrel and in
abutment with the open end of said housing, a collet surrounding
said ring means and threadedly engaged with cooperating means on
the external surface of said housing adjacent to the open end
thereof, the internal surface of said collet remote from said
cooperating means defining a cam surface for engaging said ring
means whereby, in response to adjustment of said collet relative to
said housing, said ring means is brought into sealing engagement
with said open end and behind said shoulder means, and vent means
disposed in said cylindrical housing for controlled release of
expanding gas pressures in said barrel incident to firing.
2. The invention as defined in claim 1 and wherein said split
sealing ring means comprises a single ring having the body thereof
diagonally split.
3. The invention as defined in claim 1 and wherein said split
sealing ring means comprises a pair of rings axially abutted with
each other, the abutting surfaces thereof being flat, and each of
said rings having the body thereof diagonally split, the diagonal
splits of said rings being disposed circumferentially spaced
apart.
4. The invention as defined in claim 1 and wherein said vent means
comprises a hole through said housing disposed apart from axial
alignment with the bore of said barrel.
5. In an automatic weapon having a barrel and means associated with
the muzzle end of said barrel providing an annular shoulder
adjacent to and rearwardly of said muzzle end, a blank firing
attachment for said weapon comprising a cylindrical housing having
one end thereof open and dimensioned to slideably fit over said
annular shoulder, the opposite end of said housing being disposed
coextensive with said muzzle end and said associated means, split
sealing ring means disposed for engagement with the side of said
shoulder remote from said muzzle end and in abutment with said open
end, a collet encompassing said ring means and a portion of said
housing adjacent said open end, cooperating means on said collet
and said housing for effecting axial adjustment of said collet
relative to said housing, the internal surface of said collet
defining a cam surface engageable with said ring means in response
to adjustment of said collet relative to said housing, said cam
surface being effective to collapse said ring means into sealing
engagement with said annular shoulder and said open end, and means
in said housing for venting the expanding gases in said barrel
incident to firing said weapon.
6. The invention as defined in claim 5 and wherein said vent means
comprises an opening in said housing disposed apart from axial
alignment with said barrel bore and dimensioned for controlled
release of said expanding gases.
7. The invention as defined in claim 6 and wherein said sealing
ring means comprises a single ring having the body thereof
diagonally split.
8. The invention as defined in claim 6 and wherein said sealing
ring means comprises a pair of juxtaposed rings the adjacent
surfaces thereof being flat and each of said rings having the body
thereof diagonally split, the diagonal splits thereof being
disposed spaced apart.
Description
BACKGROUND OF THE INVENTION
The present invention relates to an attachment for weapons, and
more particularly to a blank firing attachment for effecting
automatic operation of weapons.
In the art of automatic weapons, utilization of gas pressures
within the barrel is relied upon to effect automatic operation in a
manner well-known in the art. If blank ammunition is used in such
weapons, such as in the case of training operations to simulate
actual combat conditions, there is no projectile propelled through
the barrel which enables the gas system to function. Accordingly, a
blank firing attachment is applied to the muzzle end of the barrel,
the purpose of which is to take the place of the projectile
function and to enable gas pressures to build up in the barrel
sufficient to operate the weapon continuously and automatically
thereby simulating sustained fire conditions.
Although blank firing attachments are not new to the art, many are
found objectionable from the standpoint of safety, ease of
application to or removal from the weapon barrel, not universally
applicable, or they are complicated in structure, or cause
unnecessary damage to a gun barrel.
Accordingly, it is a primary object of the present invention to
provide a simple, yet highly effective, blank firing attachment for
an automatic weapon.
It is also an object of the present invention to provide a blank
firing attachment which can be easily attached to and detached from
a weapon barrel.
Another object of the present invention is to provide a blank
firing attachment which is universally applicable to and
particularly adapted for use with automatic weapons.
A further object of the present invention is to provide a blank
firing attachment for automatic weapons which conforms to maximum
safety requirements and minimizes damage to the barrels of the
weapons it is used with.
Still another object of the present invention is to provide a blank
firing attachment for automatic weapons which is of simple
structure, conducive to mass production, and yet is relatively
inexpensive to manufacture.
SUMMARY OF THE INVENTION
In accordance with the present invention, a blank firing attachment
for automatic weapons is provided which comprises a cylindrical
member having one end open for slideably receiving either the
muzzle end of a weapon barrel or other attachments associated
therewith. An annular shoulder associated with the barrel muzzle
end is utilized to attach the unit to the barrel. Split ring means
is disposed in abutment with the open end of the cylindrical
member. A collet encompasses the split ring means and a portion of
the open end and is adjustably arranged for axial movement relative
to the cylindrical member. The internal surface of the collet is
provided with a cam surface which tightens the split ring into
sealing engagement with both the shoulder and the open end of the
cylindrical member. Vent means is disposed in a cylindrical member
wall for controlled release of expanding gases within the barrel
and cylinder incident to firing the weapon.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features characteristic of the present invention, as well
as additional objects and advantages thereof, will be understood
better from the following description when read in connection with
the accompanying drawing in which:
FIG. 1 is a central, longitudinal section of a preferred embodiment
of the present invention as applied to the muzzle end of a weapon
barrel, the parts being shown in an unlocked position;
FIG. 2 is a view similar to FIG. 1 but showing the parts in a
locked position;
FIG. 3 is a side view of a single element lock ring for the blank
firing attachment, a portion thereof being shown in cross section;
and
FIG. 4 is a side view of an alternate form of lock ring, a portion
thereof being shown in cross section.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring more particularly to the drawing, wherein similar
reference characters have been used to designate corresponding
parts throughout, FIGS. 1 and 2 show a preferred embodiment of a
blank firing attachment 1 in accordance with the present invention,
as applied to the muzzle end of an automatic weapon barrel 3.
The preferred embodiment of blank firing attachment 1 is shown
applied to a conventional flash suppressor 5 which is threadably
engaged on the muzzle end of the barrel 3. The flash suppressor
includes the customary radial openings 7 and an axial opening 9 in
the end 11 thereof which function in a manner well-known in the
art. In order to effect automatic operation of a weapon using blank
ammunition, it is necessary to close off these openings. This is
accomplished by employing a cap-like body 13 in the form of a
cylinder having one end 15 closed and the opposite end 17 open. The
length of the cap-like body is at least coextensive with the radial
openings 7 from the end 11 of the flash suppressor 5. The inside
diameter of the cap-like body is greater than that of the
suppressor so that it can be slideably disposed thereover.
The flash suppressor 5 is provided with a circumferential groove 19
in its outer surface, adjacent to but rearwardly of the radial
openings and which is utilized to seal and fasten the blank firing
attachment onto the flash suppressor. The groove 19 provides a
front shoulder 20 and a rear shoulder 22, and the side 24 of the
front shoulder remote from the muzzle end of the barrel cooperates
with a split ring 31, in a manner more particularly described
hereinafter. A similar groove would be required adjacent to the
muzzle end of a barrel in the event no flash suppressor was
associated therewith.
On the external surface 21 of the cap-like body 13, adjacent to the
open end 17 thereof, there is provided a shoulder 23 having the
cylindrical outer surface thereof threaded. A collet 25 has the
internal surface 27 thereof threadedly engaged with the shoulder 23
for adjustment axially with respect to the cap-like body 13.
Adjacent to the rear end of the collet, remote from its engagement
with the shoulder, a portion 29 of the internal surface is
gradually reduced in diameter to provide a cam surface. A lock ring
31 is disposed within the collet 25 which is of a diameter slightly
greater than the external diameter of the flash suppressor so that
it can be slipped thereover in assembly. The lock ring is disposed
in abutment with the open end 17 of the cap-like body 13 and it is
provided with a diagonal cut or slit 33 to facilitate reducing its
diameter under the influence of the collet cam surface 29. Although
the lock ring may be of a single ring type having a circular cross
section, as shown in FIG. 3 of the drawing, an alternate embodiment
of lock ring which is a split ring 35, as shown in FIG. 4, can also
be used. In the latter case, each half has a semi-circular cross
section and the respective flat sides 37 of the two ring halves are
disposed adjacent to each other. Each one of the ring halves is
provided with a diagonal cut or slit 39 the same as cut 33 in the
single ring embodiment. Preferably, the respective cuts in the two
halves should be spaced apart in order to provide a more effective
gas seal.
The cap-like body 13 is provided with a small hole 41 in the closed
end 15 thereof. It is disposed preferably away from the center line
of the bore axis so that expanding gases do not have an exit path
straight through. The hole 41 is of a size which will effectively
reduce expanding gas pressures within the barrel incident to blank
firing but maintain sufficient pressure to sustain automatic fire
of the weapon in a manner well-known in the art.
Application of the blank firing attachment to the barrel of a
weapon utilizing a flash suppressor is as follows. The blank firing
attachment is assembled with the collet 25 threadedly engaged with
the cap-like body shoulder 23, and with the lock ring loosely
disposed within the collet, as shown in FIG. 1 of the drawing. The
assembly is mounted over the flash suppressor sufficiently to
dispose the lock ring axially opposite the suppressor groove 19 and
in abutment with the open end 17 of the cap-like body. The collet
is rotated relative to the cap-like body thereby to advance it
forwardly. This movement of the collet engages the internal cam
surface 29 thereof with the lock ring to reduce the diameter
thereof thereby moving the lock ring into the suppressor groove.
Thus, as the collet is further moved forwardly, a gas seal is
effected between the collet, the sides of the suppressor groove 19
and the open end 17 of the cap-like body, thereby to seal the
suppressor openings 7 and the barrel bore.
Although but two preferred embodiments of the present invention
have been shown and described herein, it will be recognized by
persons skilled in the art that variations and changes are possible
within the spirit and scope of the present invention. Therefore, it
is respectfully requested that the present invention not be
regarded as limited in scope but include all changes and
modifications coming within the terms of the claims hereof.
* * * * *