Abstract: A shotgun cartridge (1) has an armour piercing shell (11) which includes a main charge (17) arranged to be detonated or exploded by direct percussion of a primer (12). The cartridge (1) includes a bore safe cylindrical arming device (16) integrally formed with the obturator (6), which interrupts the detonation process after detonation of the primer (12). The arming device (16) is arranged to separate from the shell, to arm the shell, after firing of the shell (11) from the barrel of a gun, and the shell (11) includes an open base or rear portion to prevent shrapnel being thrown to the rear on detonation.

Abstract: In an ammunition round a substantially full bore diameter bullet has a plurality of elongate grooves either helically formed or parallel with the longitudinal axis of the bullet and a sabot which has a body and fingers which engage with the grooves and seal the bullet in a casing, the sabot having a slightly larger diameter than the bullet so that the sabot is engraved by the rifling slots in the barrel through which the round is to be fired, in order to rotate the bullet. In alternative constructions the grooves contain elongate elements or a plurality of spherical elements to prevent the conically tapered slug or bullet from tilting or cocking in the barrel after firing.

Abstract: In an ammunition round a substantially full bore diameter bullet has a plurality of elongate grooves either helically formed or parallel with the longitudinal axis of the bullet and a sabot which has a body and fingers which engage with the grooves and seal the bullet in a casing, the sabot having a slightly larger diameter than the bullet so that the sabot is engraved by the rifling slots in the barrel through which the round is to be fired, in order to rotate the bullet. In alternative constructions the grooves contain elongate elements or a plurality of spherical elements to prevent the conically tapered slug or bullet from tilting or cocking in the barrel after firing.

Abstract: This invention relates to magazines for guns. The drum magazine of the present invention comprises one or two generally cylindrical drums with openings for the exit of cartridges from within the drum. A spring driven rotor within the drum carries two concentric rings of cartridges in a channel defined by the outer circumference of the rotor and the interior of the cylindrical drum wall. The rotor engages the inner concentric ring of cartridges and each cartridge in the outer ring of cartridges is forced to move by contact with a cartridge of the inner ring. During feeding, the cartridges are advanced as two rings until they meet the cam blade, which gradually forces the cartridges into a single column which moves approximately twice as fast as the velocity of the cartridges in the rotor. When the last cartridge leaves the rotor during feeding and enters the exit passage, a follower arm is provided to continue to push the last cartridge out of the magazine.

Abstract: In an ammunition round a substantially full bore diameter bullet has a plurality of elongate grooves either helically formed or parallel with the longitudinal axis of the bullet and a sabot which has a body and fingers which engage with the grooves and seal the bullet in a casing, the sabot having a slightly larger diameter than the bullet so that the sabot is engraved by the refling slots in the barrel through which the round is to be fired, in order to rotate the bullet. In alternative constructions the grooves contain elongate elements or a plurality of spherical elements to prevent the conically tapered slug or bullet from tilting or cocking in the barrel after firing.

Abstract: A gun having a trigger mechanism comprising a pivotally mounted trigger (73) which is connected to rotate a pivotal sear and a reciprocal bolt carrier assembly having lugs (325) which are arranged to engage with the rear of the sear and a notch (717) in the top of the sear. Mounted on the pivotal axis of the trigger is a prop member (745) which is arranged to cooperate with an L-shaped nose (720) of the sear so that when the trigger is pulled to rotate the sear in a first direction out of engagement with the lugs (325) the prop member (745) is initially prevented from moving with the trigger by the nose (720) and when the lugs are released by the sear the sear is further rotated in the first direction by the lugs contacting the upper sear surface to free the member to move toward the trigger and under the nose (720). The prop member is then positioned under the nose (720) and thereby prevents the sear from rotating in a direction counter to said first direction until the trigger is released.

Abstract: A bolt carrier assembly has a housing (300) for supporting a bolt (317) and a P cross-sectionally shaped member (301) having the longer side of the P-shape secured to the housing, the P-shaped member being forwardly extended with respect to the bolt. The main drive spring (307) is located alongside the wrapped-over portion of the P-shaped member which main drive spring is arranged to provide motion to the housing and P-shaped member. An anti-bounce weight (354) is mounted inside the wrapped-over part of the P-shaped member and has a spring at one end which is compresed by the anti-bounce weight when the P-shaped member is suddenly retarded by the housing to which it is attached striking the barrel assembly. A latch (326-329) is spring biassed and shaped and dimensioned to interleave locking lugs (322) on the bolt (317), the latch being longitudinally retractable with respect to the housing.

Abstract: A gas operated gun having a receiver (1) including a rear wall (100) at one end and a barrel (10) at the other end and a bolt carrier assembly (3) reciprocal within the receiver is arranged to co-operate with a main drive spring (307) that urges the bolt carrier assembly toward the barrel. The gun is designed so that in one aspect of the invention on an automatic cocking cycle the bolt overtravels the cartridge feed station by an amount equal to or greater than the overall length of a live cartridge.In a further aspect, the gun is additionally designed using parameters calculated such that a substantially constant reaction is felt by a user. The parameters involved are essentially the product of sprung weight (the total weight in kg. of all components driven by the main spring).times.springing force (an average value of spring force that accelerates and retards the sprung weight).times.cycling distance (the length of allowable travel of the bolt carrier assembly in meters) is equal to (0.51).sup.2 .times.0.

Abstract: A sear actuator has a rotatable cylinder (770) mounted between opposing side walls of the receiver (1) and a slidable rod (771) extending transversely to the cylinder. The actuator is arranged so that in one position the trigger applies a rotating force to the sear through the slidable rod (771). In a different position of the cylinder (770) the slidable rod is moved out of the path of the force exerted by the trigger and the trigger abuts a wall of the cylinder and thus the sear is rendered inoperative.

Abstract: A drum magazine for a gun has a circularly cross-sectioned housing (40) with a feed throat (415) extending from the housing for releasing cartridges and concentric sprockets (42, 43, 44) having serrations nesting cartridges. A torsion spring (46) is arranged to rotatingly drive the sprockets and feed ramps (434, 441, 455, 455', 471, 471') are provided for assisting the cartridges to traverse from the sprockets to the feed throat (415).The feed throat has two lips and one of the lips (417) is pivotally biassed to act as a one way valve such that in one position cartridges are prevented from being ejected in a direction perpendicular to the housing axis and yet cartridges may be inserted into the housing in a direction perpendicular to the housing axis.

Abstract: A sear buffer having a U-shaped member with bowed longitudinal arms, the free ends of the arms being arranged to locate a sear therebetween. The U-shaped member is located by a block, a rod and further rod, the bow in the arms being temporarily reduced when the sear is contacted by the lugs of a reciprocating bolt carrier assembly.

Abstract: A drum magazine for a gun has a housing with a feed throat extending from the housing and within the housing are mounted concentric sprockets. The sprockets have serrations for nesting cartridges and each sprocket is independently rotatable with stops for limiting the rotation of the outer sprocket and stops limiting rotation of the intermediate sprocket. A latch is arranged to prevent rotation of the outer sprocket in a counter direction to the direction of feeding cartridges out of the magazine until the intermediate sprocket is rotated in the counter direction a predetermined amount. A connector is connected to the outer sprocket and passes through the outer sprocket to engage with the cartridges nested in the intermediate sprocket so that by virtue of the connector, the sprockets rotate together. A similar connector is provided between the intermediate sprocket and the inner sprocket. A U-shaped pusher is provided to push the last few remaining cartridges in the magazine out of the feed throat.