Abstract: Provided is a handguard attachment mechanism for use with a firearm using a standard AR-pattern barrel nut having a substantially cylindrical portion with an axial length and an enlarged diameter radial flange at a forward end. The handguard includes a substantially tubular handguard with proximal and distal ends. The proximal end includes a longitudinal slot extending from the proximal end toward, but not to, the distal end. A pair of clamping lugs, one positioned on each side of the slot adjacent the proximal end, have means for adjustably drawing the clamping lugs together to narrow at least a portion of the longitudinal slot. A circumferentially incomplete barrel nut bushing is configured to fit on the barrel nut.

Abstract: The present invention provides matched upper and lower firearm receivers and method of manufacturing the same. An upper receiver has a forward lug and a rear lug. A lower receiver has forward ears and rear sidewalls that form a pocket. When the upper and lower receivers are positioned together, the forward lug fits between the lower receiver ears and the rear lug fits into the pocket between the sidewalls. Forward openings are formed in axial alignment through the ears and forward lug. Rear openings are formed in axial alignment through the rear sidewalls and the rear lug. Reinforcement sleeves are fitted into the forward openings of the ears and forward lug and into the rear openings of the sidewalls and rear lug.

Abstract: Provided is a handguard attachment mechanism for use with a firearm using a standard AR-pattern barrel nut having a substantially cylindrical portion with an axial length and an enlarged diameter radial flange at a forward end. The handguard includes a substantially tubular handguard with proximal and distal ends. The proximal end includes a longitudinal slot extending from the proximal end toward, but not to, the distal end. A pair of clamping lugs, one positioned on each side of the slot adjacent the proximal end, have means for adjustably drawing the clamping lugs together to narrow at least a portion of the longitudinal slot. A circumferentially incomplete barrel nut bushing is configured to fit on the barrel nut.

Abstract: A firearm having a barrel, an integral gas block operably mounted on a portion of the barrel and a muzzle end device mounted on an end of the barrel. The barrel portion has an outside diameter equal to and preferably greater than the greatest outside diameter of the muzzle end device. The gas block has an inner diameter such that the block is slidable along, onto or off the barrel, and over and beyond the muzzle end device while it is mounted on the barrel. Methods are disclosed.

Abstract: A warhead casing and method of inserting compartments into a warhead casing. The system includes a nose section, a tail section, and a tubular body section therebetween. The sections define a lengthwise axis of the casing. The system further includes a first plurality of compartments radially arranged along a perimeter of the tubular body section. The first plurality of compartments form a first cross-sectional layer. The system further includes a central cavity extending along the lengthwise axis of the casing, the central cavity being defined at least by an inner surface of the first plurality of compartments or the tubular body section.

Abstract: The present invention provides matched upper and lower firearm receivers and method of manufacturing the same. An upper receiver has a forward lug and a rear lug. A lower receiver has forward ears and rear sidewalls that form a pocket. When the upper and lower receivers are positioned together, the forward lug fits between the lower receiver ears and the rear lug fits into the pocket between the sidewalls. Forward openings are formed in axial alignment through the ears and forward lug. Rear openings are formed in axial alignment through the rear sidewalls and the rear lug. Reinforcement sleeves are fitted into the forward openings of the ears and forward lug and into the rear openings of the sidewalls and rear lug.

Abstract: The present invention provides a fluted firearm barrel and method of making a fluted firearm barrel. An elongated barrel has an exterior surface. A plurality of longitudinally extending, circumferentially spaced apart grooves are formed in the exterior surface. Each groove varies in width multiple times along the length thereof, such that each groove has at least two widened portions with a narrowed portion therebetween.

Abstract: The present invention provides a fluted firearm barrel and method of making a fluted firearm barrel. An elongated barrel has an exterior surface. A plurality of longitudinally extending, circumferentially spaced apart grooves are formed in the exterior surface. Each groove varies in width multiple times along the length thereof, such that each groove has at least two widened portions with a narrowed portion therebetween.

Abstract: A warhead casing includes a nose region, a tail region, a tubular body region, and a central cavity extending along a lengthwise axis and having a first axial end and a second axial end. An aft wall is formed integrally with the tail region and extends radially toward the lengthwise axis to define the second end of the central cavity, and includes an aperture configured to receive a fuse device. A method of manufacturing a warhead casing includes forming a nose portion, a body portion, and a tail portion. The tail portion includes a circumferential outer wall defining an inner cavity, and an aft wall integrally formed with the circumferential outer wall and extending radially inward to define an axial end of the inner cavity. At least one of the nose portion or the tail portion is joined to the body portion.

Abstract: A passive safety for an AR platform firearm includes a sliding or pivoting rotating safety which is normally active to prevent trigger movement as would cause the firearm to discharge, and even when any active safety on the firearm is in a “fire” position. The passive safety is deactivated when an operator grips the firearm in a normal position to engage and pivot the trigger to discharge the firearm. Alternative embodiments are disclosed.

Abstract: A warhead casing includes a nose region, a tail region, a tubular body region, and a central cavity extending along a lengthwise axis and having a first axial end and a second axial end. An aft wall is formed integrally with the tail region and extends radially toward the lengthwise axis to define the second end of the central cavity, and includes an aperture configured to receive a fuse device. A method of manufacturing a warhead casing includes forming a nose portion, a body portion, and a tail portion. The tail portion includes a circumferential outer wall defining an inner cavity, and an aft wall integrally formed with the circumferential outer wall and extending radially inward to define an axial end of the inner cavity. At least one of the nose portion or the tail portion is joined to the body portion.

Abstract: A passive safety for an AR platform firearm includes a sliding or pivoting rotating safety which is normally active to prevent trigger movement as would cause the firearm to discharge, and even when any active safety on the firearm is in a “fire” position. The passive safety is deactivated when an operator grips the firearm in a normal position to engage and pivot the trigger to discharge the firearm. Alternative embodiments are disclosed.

Abstract: Disclosed is an upper receiver assembly for use with an AR15-type lower receiver. The upper receiver assembly includes a monolithic upper receiver and forearm housing. A barrel has a breech end, a muzzle end, a bore axis, and a barrel trunnion at the breech end having a lug for direct connection to the lower receiver using the pivot pin. It includes a bolt carrier assembly, having a longitudinal slot and rail engagement with the upper receiver housing on which the bolt carrier assembly slidably reciprocates, and a long-stroke gas-piston actuation system. A recoil spring assembly is housed within the monolithic upper receiver and forearm housing and extends coaxially with the longitudinal axis of the gas-piston actuation assembly. The barrel trunnion and gas block are configured for engagement with the upper receiver and forearm housing with longitudinal keyway features.

Abstract: Disclosed is an upper receiver assembly for use with an AR15-type lower receiver. The upper receiver assembly includes a monolithic upper receiver and forearm housing. A barrel has a breech end, a muzzle end, a bore axis, and a barrel trunnion at the breech end having a lug for direct connection to the lower receiver using the pivot pin. It includes a bolt carrier assembly, having a longitudinal slot and rail engagement with the upper receiver housing on which the bolt carrier assembly slidably reciprocates, and a long-stroke gas-piston actuation system. A recoil spring assembly is housed within the monolithic upper receiver and forearm housing and extends coaxially with the longitudinal axis of the gas-piston actuation assembly. The barrel trunnion and gas block are configured for engagement with the upper receiver and forearm housing with longitudinal keyway features.