Note: Descriptions are shown in the official language in which they were submitted.
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This invention rel~stes to a man-portable multi-sllot weapon capable
o~ firing relatively Largc calibre projectiles at a rapid rate ancl to a
conversion unit for use in providing single-shot weapons with multi-shot ~`~
capa bi l i ty
At present, the only large calibre man-portabLe weapons are single~
shot, breech loading types such as the American 40mm M79 grenade launcher
and the 38mm Fecleral Gas Gun. These weapons have relatively slow rates cif
fire which is a drawback due to the short range of the weapon. This means
that a moving target can cover the engagement distance or retreat out of ` `
range in a relatively short period of time. Single-shot, breech loading
weapons also have disadvantages insofar as the "zeroing-in" aspect is ;
concerned. In other words, by observation of the point of impact of a shot, ~
one can make corrections to the line of sight so as to bring the next shot ~ ;;
on target. More specifically, the weapon must be taken from the shc~ulder ~;
to reload between each shot, thus taking the eye of the user off the target. ~;
Secondly, the re-loading time is considerably longer. These two aspects
combine to reduce the abili~y to effectively use the informatlon~gained from `~
the obse~rvation of the point of impact of one shot for zeroing-in the
succeeding-shots.
2~0 Thus, a rapid rate of fire would considerably increase the effective~
ness of the weapon, especially when dealing with highly mobile targets. A -~
rapid rate of fire combined with the ability to fire a numbe~ of rounds with-
out removing the line of sight from the traget greatly improves the
effectiveness of the correction mentioned above, thereby considerably improving
the hit probability of succeeding rounds. This is especia]ly true when
engaging moving tragets where an estimation of lead is required. Moreover,
when employing gas, smoke or illuminating munitions, rapid fire capability ;~
would enable the production in minimum time of the intensity of gas, smoke
or light required in a particular situation.
Accordingly, it is an object of the invention to provide a man-
portable multi-shot weapon capable of firing relatively large calibre ;
projectiles at a rapid rate.
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It is another object of tSle invention to prQvide a conversion unit
lor l)rovidin~ r~ ly lar~c cal;brc singk~-sllot wcal)ons with multi-sllot
capability.
Thus, according to one aspect of the invention, a man-portable
multi-shot weapon is provided whicll is capable oE firing relatively ]arge
calibre projectiles at a rapld rate, comprising a barrel, a breech assembly,
the breech assembly including a frame on which the barrel i9 moun~ed and a ~;;
lateral opening through opposite sides of the frame for receiving a magazine,
the magazine having a plurality of aligned chambers to accomodate relatively
large calibre projectiles, magazine aclvance means for laterally advancing the
magaæine through the breech opening in such a manner that the chambers are
successively brought into a firing position in alignrnent with the barrel, and ~;;
a firing means for firing a projectile when in the firing position. `
According to another aspect of the invention, a conversion unit for
use in providing relatively large calibre single-shot weapons with multi-shot
capability is contemplated, said single-shot weapon comprising a barrel to be
removed and discarded and a stock and firing means to be modified for use with ;
said conversion unit, said conversion unit comprising a barrel, a breech
assembly including a frame on which the barrel is mounted, and a lateral open~
ing through opposite sides of the -frame for receiving a magazine having a
plurality of aligned charnbers to accornmodate relatively ~arge calibre project-
iles, magazine advance means associated with the breech assembly, and means
for connecting said conversion unit to said modified stock and firing means, ~ -
said magazine being adapted to be received in and to be laterally advanced
through the breech opening by said magazine advance means, in such a manner
that the chambers are successively brought into a firing position in alignment
with the barrel. ~- -
In the drawings which serve to illustrate a preferred embodiment of
the invention;
Figure 1 is a side elevation of the invention, illustrating the ~`~
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operation of the advancing mechanism and the assembly thereof;
Figure 2 is a top view of the invention, depicting a magazine
engaged in the weapon;
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I`igure 3 i9 <I fr-)rlt view 0~ the invention depLcting a magazlne
engagccl in tllc weapon;
Figure 4a is a side elevation oE the invention with pistol grip,
illustrating ~he deLails of the construction of the weapon, including a
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loaded magazine engaged therein;
Figure 4b is a simllar side elevation of the invention with pump
type grip;
Figure 5 is a side elevation of the invention which illustrates
the field stripping procedure;
Figure 6 ls a rear view of a magazine according to the invention,
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which illustrates the cartridge cover;
Figure 7 is a top view of a magazine according to the invention
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- illustrating the cam track; and
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Figure 8 is a series of side elevations which illustrate the , ~ `
conversion of an existing single-shot weapon to a multi-shot weapon. `
Referring specifically to the drawings wherein like reference
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numerals denote like parts, the weapon is seen to comprise a barrel 4, ;
including a bore 4a, a breech assembly 31, the breech assembly 31 including `
a breech frame 14 on which the barrel 4 is mounted and a lateral breech ~ ~
20 opening 24 through opposite sides of the breech frame 14. The breech opening ~- ;
24 is adapted to receive a magazine 7 having a plurality of aligned chambers
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25, conveniently three, to accomodate reiatively large calibre projectiles,
for example, 38mm and 40mm. The magazine 7 is adapted to be laterally
- advanced through the breech opening 24 by a magazine advance means in such
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a manner that the chambers 25 are successively brought into a firing position ~``
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in alignment with the bore of the barrel 4a.
A conventional firing means associated with the breech assembly
for firing a projectile in the firing position is also provided.
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Specifically, the firing means comprises a spring loaded strlker rod ~`
30 37 ~arryin3 a firing pin 33 which is pulled backwarde under the action of
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a trigger 39~ When thetrigger 39 i8 pulled back a certain distance, the
striker rod 37 i~ released forwardly under the action of a release cam
40 and the firing pin 38 i9 forced into the prlmer cap of a cartridge in
the firing position, causing a projectile to be fired. Access to the ;~
firing mechanism i9 afforded by a removable cover plat~e 45.
- A safety catch ~ is provided which i8 slideable in a grove
betwean an engaged position wh~rein the strikerr rod 37 i9 prevented
from moving backwards when the trigger 39 is pulled; and a disengaged
position wheraas the striker rod is free to move backwards under the
action of the trigger.
More specifically, the magazine 7 i8 of rectangular configuration,
including a top 50, a bottom 51, long 52 and short 53 sides. The chambers `~
25 are defined by laterally aligned openings through the long sides 52.
Track plates 36 are bonded to the top 50 and bottom 51.
Conveniently, the track plates 36 are pinned to the magazine 7 by
means of plastic pins 41 which pass through holes 42 in the track plates
36. The pins 41 are integral with the magazine 7. With the track plates
36 in position, that i8, with pins 41 extending through the holes 42, a
heated rod with a concave tip 44 is used to mushroom the ends of the pins ~ ;
as at 43 to securely hold the plates 36 in place. At least the track plated
bonded to the bottom 51 includes a cam track 26 molded therein.
Conveniently, a corresponding cam track 26 is provided in the top and bottom `~
track plates 36 80 that the magazine may be in3erted into the breech opening
24 with either the top or bottom downwards in order to minimize the loading
time.
~ The main magazine parts are such that they can be molded from a suit- ;~
able plastics material, for example, polycarbonate, thus reducing production
time and costsO This is especially true of the track plates 36. However
it will be appreciated that the cam tracks 26 could be machined into the
surface of the magazine or of the track plates, but at considerable additional
expen3e.
The magazine advance means comprises a cam pin 27 directly linked to
foregrip 28, which may be in the form of a pistol-type grip as shown in
Figure 4a or a pump action-type grip as shown in Figure 4b, depending upon
the requirements of the user.
s~
~ 9 seen in Yigures 4a and 4b, tlle cam pin 27 is carried by a pin arm
15. The pin arm 15 is detachably linked to a slider arm 16 via retaining
means 15a. The slider arm 16 is ridgidly mounted on the Eoregrip 28. The
foregrip 28, in turn is mounted on a slider frame 8 whlch is welded to the
breech frame 14.
A slider arm cover 17 and a pin arm cover lg serve to protect the
slider arm - pin arm assembly. The slider arm cover 17 is welded to the
slider fra~ 8. The pin arm cover 19 is detachably held at one end to the
breech assembly 31 by a catch mechanism 18 and at the other end by a re-
taining means 19a in the form of a pair of spared lugs which engage slots
in the slider fram~ 8.
As best seen in Figure 5, the foregrip 28, pin arm 15, and pin arm
cover 19 are designed such that rapid field stripping of the magazine advance
mechanism is possible with no tools being required.
When the foregrip 28 is moved backwards and forwards, the cam pin 27
also move~ backwards and forwards in a slot 29 in the breech opening 24. The
backward and forward positions are illustrated in Figure 1 as A and B, respect-
ively. When the magazine 7 is inser-ted into the breech opening 24, the cam
track 26 engages the cam pin 27. The cam track 26 is laid out such that when
the foregrip 28 is moved backwards and forwards, the magazine 7 is advanced
laterally or sideways through the breech opening 24 so tha-t the next shot
to be fired becomes aligned with the barrel 4. Conveniently, the cam track
26 is of zig-zag configurationO
The barrel 4 is threaded into the breech frame 14 at 60 as s~en in
Figures 4a and 4b, such that the clearance between the barrel 4 and the
magazine 7 can be easily adjusted. This allows for the elimination of any
excess Flearance which may have occured as a result of an accumulation of
manufacturing tolerances.
The breech assembly 31 acts as the support and h~using for the slider
mechanism. The barrel 4 is not used in any way as a supporting member for
3~
the Eoregril) 2~ or the S~ er IlleCllalli9m, fl~ iS often the case with other
~enl)()l~ sys~eills. 'Ill~ls, ~In~crewil~g the harrc~l is th(! only opercltion required
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for its removal.
A sprin~ actlvateti F)osition plunger 6 is used to eliminate any
undesired movement between the magazine 7 and the breech assembly 31 when a ~`
projectile 22 is in the firing position. The plunger is forced by a spring
32 into indentations in the magazine 7 such that the chambers 25 are more
precisely aligned with the barrel 4. The plunger design is unique in that -~ ~ ;
it uses the same spring and cavity as the breech latch 5, thus elirninating
the need for another spring.
The projectiles 22 are held in place in the magazine 7 by a sliding
cover 34 as seen in Figure 6. The cover 34 also ac-ts as a protective shield
for the primer caps of the projectiles which would otherwise be dangerously ' ~
exposed. The cover fits into grooves 35 in the top and bottom faces of the ; ~ -
magazine 7. The grooves 35 extend the length of and are adjacent one of the
long sides 52 of the magazine. The cover 34 overlaps the portion of the top
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and bottom surface between the grooves 35 and the long side and includes ;
lugs 37 which hold the cover in the grooves by a light interference fit. As
the magazine 7 advances sideways or laterally through the breech opening 24, ;~`
the cover 34 contacts the breech frame 14 and is pushed across the rear face
of the rnagazine, thus exposing the primer caps of the projectile~ to the `
action of the firing mechanism.
Rifled sleeves 21 may be inserted into the magazine chambers 25.
The sleeve rifling allows the projectile 22 to acquire spin smoothly during
launch, thus avoiding damage to its engraving band. If a projectile were
allowed to gain a high linear velocity in a smooth bore cartridge charnber
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without being spun, the abrupt engagement of the gun barrel rifling might
generate angular acceleration stresses high enough to shear its engraving
band~
A button released locking catch 10 is incorporated into the fore-
grip 28 so that in order to move the foregrip, the release button 11 must
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firs~ be dcl~rec;se(l~ 'i'l~i.9 locking catch lO prevelltY movem~nt oE the fore-
~rill 28 wllell t'iring Llle We.ll)OII.
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A front sight 2 is attached to the barrel 4 by clamping action such
that iE the weapon is dropped, t:he sight can turn around the barrel without
damage. The sight 2 can then be re-aligned by unscrewing the clamp screw I ;
3a, positioning the sight correctly, and then re-tightening the clamp screw
3a. The front sight screw 3 is adjustable up or down ~o provide for
adjustment of the sighting system.
A rear sight 30, mounted on the breech cover 1', is of the folding
leaf type with adjustment to be provided for range and drift.
According to another embodiment of the inrentionJexisting single-
shot weapons, for example the 38mm Fecleral Gas Gun, may be converted to `multi-shot capability. More specifically, as seen in Figures 8A to 8D,
8A represents the 38mm Federal' Gas Gun, 8B illustràtes the same gun with the
barrel removed and discarded, 8C shows the same weapon having been modified ;
by cutting away the existing latch lugs 5a and replacing them with reinforced '
ones 5b, and re-locating'pivot point 5c to 5d, to enable connection with the
converslon unit illustrated in 8D. The converslon unit may then be connected
to the modified weapon of 8C.
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The conversion unit comprises a breech assembly 31 including a
barrel 4, a frame 14 on which the barrel 4 IS mounted,' and a lateral opening
24 through opposite sides of the frame 14. Magazine advance means comprising
a reciprocating cam pin 27 associated with the breech assembiy 31, and means
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for connecting the conversion unit to said modified stoclc and firlng me~ans
23 at 5b and 5d.
This feature should prove to be economically attractive to parties
who already possess these single-shot weapons and wish to convert them to
multi-shot capability. `~
The connecting means comprises a breech latch 5 and spaced lugs 6a
mounted on the breech frame 14~ Lug 5d, on the modified stock and firing
means 23 is located between the lugs 6a and a retaining pin is inserted ~; ;
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througl~ e l~ ; s~lcll ~ t th(! hreecll nsserl)l)ly i~ llivotally c(-lnnccte(l to
tlle modiliecl ~ock and iirirlg meall~ 23. Iile breecll laLch 5 e~ngages with
latch lug 5b to rigi(ily connect the breech assembly to the modLfied stock
and firing means 23.
By réleasing the breech latch 5, the breech fr~ne 14 can be broken
open for single shot firing of rounds whose length is longer than that of
the magazine 7. This is a feature not possessed, by most other multi-shot
systems which are usually limited to rounds of one particular length.
A single chambered magazine may also be used to re-convert the ~ -
weapon without further modification to the single shot mode. In this
configuration the magazine is simply a single chamber segment of the three-
shot magazine clescribed previously. It has cam tracks on its upper and
lower surfaces iclentical in geometry to the first cycle of the cam tracks
of a three shot magazine. Accor~dingly, the single shot magazine is inserted
into the weal)on in the same manner
To load when using the single shot magazine, the breech latch 5 is
released and the breech opened such that the spent cartridge case can be ~ `
removed and a fresh one inserted. In this configuration, the weapon becomes
very similar to the existing ~S 40mm M-79 and the 38mm Federal Gas Guns
(Fig. oa) already in service. Thus, this system may be considered as two
weapons in one; a single shot breech loading glm, and a multi-shot magazine
loaded gun. This flexibility should allow for more optimum matching oE the
weapon system to the requirements of a given tactical situation. -~
On loading the weapon, a fully loaded magazine 7 is lnserted into -
the breech opening 24, thus eliminating the need for opening the gun and
individually inserting projectiles as is the case with a conventional
revolver. This feature considerably increases thç rate of fire of the
weapon. ~ ~;
On firing, the magazine 7 acts as a part of the barrel 4, elimina-
30 ting the need for any reciprocating breech parts as is required in rnost ;
other types of repeating guns for chambering and extracting the cartridge
cases. In this respect, it is similar to a conventional revolver.
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firing the laSL 9l1O~ ~he magazine is ej(cted Irom tlle weapon, thlls
e].ilnillclting Lhe n(~c(l For opening the g-ln and extractillg the cartridge cases
as is requirecl witll a conventional revolver. This feature considerably
increases the weFIl)onls rate of fire.
~ lore speciLically, to load the weapon, the ~ollowing operat;ons are
reguired. First the safety catch 25 is moved to the "Safe" position. The
foregrip release button 11 is depressed and the foregrip 28 is pulled back-
wards and left in the rearward position. This action ejects an empty
magazine and positions the cam pin 27 for insertion of a new magazine 7.
The new magazine 7 is inserted into the breech opening 24 until it engages
the cam pin 27. The foregrip 28 is then pushed forward until the locking
catch 10 locks into position. The first round in the magazine is now
aligned with the barrel and ready to be fired. After a shot has been fired,
a fresh round Is brought into the firing position by depressing the fore-
grip release button 11 and moving the foregrip 28 backwards and forwards.
When firing m~mitions whose length exceeds that of the magazine 7
or when using the singLe shot magazine, the breech is broken open between ; ;
each shot for removal of the empty cartridge case and insertion of a new
one. This is done by pushing upwards on the breech latch 5 which allows
the breech to open.
The weapon has proven to be compatible with existing 38mm and 40mm,
combat, practice, and internal security ammunition. This includes both
spin stabilized and non-spin stabilized projectiles.
Rapid conversion of the weapon ~rom one calibre to another or from
a rifled system to a smooth-bore system is easily performed in the field
with no special tools being required. All that is required is to manually
unscrew the barrel 4 and replace it and its corresponding magazine 7 with
a barrel and magazine combination having the desired alterna-tive
characteristics.
In view of the various embodiments described hereinabove, it should
be apparent to those skilled in the art that the present invention ~ay be
émbodied in forms other than those specifically described herein without
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del)artin~ rr(~m tlle sl)irit or central charclctcristicLi of tlle invention.
'I`tlll!i, Lll(' S~ i ri.C (`Illl)O(Iilll('lltS (~ sCril)C`d ilt~OV(' clrC! to bc considcred in
all respects as illustrative and not restrictive.
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