Abstract: In an accessory mount mechanism being releasably and adjustably assembled to the accessory mount rail of a firearm a lever-actuated clamping mechanism employs an upwardly facing clamping force adjustment member that is manually adjustable by the firearm user without the use of tools of any kind. A locking lever is pivotally mounted to a lateral platform of a mount base by means of an integral spindle shaft that projects upwardly from a cam plate that is fixed to the locking lever. The spindle shaft defines a non-circular section that is engaged by a corresponding non-circular drive receptacle of a drive washer member that is urged upwardly within an insert member of the mount base by a spring member. A manually actuated adjustment member is threaded to the spindle shaft and faces upwardly for ease of visual location and manual rotation by the user of the firearm.

Abstract: A propellant gas energized firearm has a gas supply passage conducting propellant gas from a gas port of a firearm barrel to an actuating chamber of a bolt carrier and bolt group having an actuating chamber. A gas key member is mounted to the bolt carrier and defines a part of the gas supply passage and has an opening intersecting the gas supply passage. A gas adjustment member is selectively moveable within the gas adjustment opening and has a gas interruption member projecting into the gas supply passage. The gas adjustment member is rotatable within the gas adjustment opening for selectively positioning the gas interruption member within the gas supply passage to selectively control the characteristics of the propellant gas delivery to the actuating chamber of the bolt carrier and bolt group.

Abstract: A suppressor and flash hider device for firearms defines primary and secondary propellant gas paths that function simultaneously to quickly decrease gas pressure within the tubular housing of the suppressor to minimize blow-back toward the firearm user. The tubular housing has a collet-like firearm clamping system that establishes symmetrical clamping that will not tend to force the suppressor off coaxial alignment with the firearm barrel to which is mounted. A front wall mounted to the housing defines a central projectile port through which propellant gas also passes and defines an array of angularly oriented discharge passages for discharging propellant gases from the secondary propellant gas path forwardly and angularly toward gas being discharged from the projectile port of the front wall.

Abstract: A firearm noise suppressor and flash hider device having a tubular housing having left hand threaded components. A suppressor mount securing and aligning the tubular housing relative to a firearm barrel. A number of propellant gas handling members within the housing define aligned projectile ports and baffle chambers to permit projectile movement and slow the progress of propellant gas as it traverses the internal chamber. These gas handling members define primary and secondary flow paths within the housing to divide the propellant gas discharge from the barrel and minimize gas pressure and volume of flow, resulting in lower propellant pressure, minimized noise and propellant flash. The primary and secondary flow paths each have separate discharge openings at the forward end of the suppressor.

Abstract: A cartridge gas energized firearm mechanism has a receiver assembly having upper and lower receivers. A bolt carrier is moveable within the upper receiver and has a wall structure having a planar gas key seat surface intersected by a gas port. A gas key is mounted to the bolt carrier and has a planar gas key surface in face-to-face seating engagement with the planar gas key seat surface of the bolt carrier, thus establishing a planar surface interface. The gas key has a cartridge gas supply passage in gas communication with the gas port. A tubular seal member is positioned in sealing engagement within seal receptacles of the bolt carrier and gas key and prevents cartridge gas leakage through the planar surface interface.

Abstract: To permit ease and efficiency for the extraction of spent cartridge cases from the cartridge chamber of a firearm barrel within a wide range of temperature conditions, the internal tapered surface of the body region of a cartridge chamber is prepared by establishing circumferentially spaced longitudinal straight or curved regions of the internal surface finish to create an internal cartridge chamber geometry having gradually tapered spaced longitudinally relieved linear or spiral areas having longitudinal linear or spiral lands between each of the relieved areas. The circumferentially spaced lands develop controlled impedance to rearward cartridge case movement on cartridge firing to effectively protect the bolt and extractor mechanisms of the firearm against early failure.

Abstract: A firearm having modular components that can be assembled under field conditions, by using simple tools. Upper and lower receivers are assembled by pins and a barrel and gas tube are secured to the upper receiver by a barrel nut. Mounting flanges of the upper receiver and a handguard are secured in reliable assembly by a manually actuated clamp mechanism having a clamping condition releasably securing the handguard to the upper receiver and having a releasing condition permitting separation of the handguard from the upper receiver. A pocketed soft protective container receives and protects the modular firearm components until firearm assembly takes place.

Abstract: A detachable handguard for firearms having a receiver defining a handguard mounting flange. Clamp members have hook-like ends that engage the handguard mounting flange and are attached to clamp actuating levers that are pivotally mounted to the handguard. The clamp members are positioned in clamping engagement with the mounting flange and are pivoted to clamping positions to force the handguard into tight assembly with the receiver and to move the connection of the clamp members with the actuating levers over-center, thus causing the clamp actuating levers to remain at their clamping positions. Lock members secure the clamp actuating levers at their clamping positions.

Abstract: A tactical firearm having upper and lower receivers that are releasably connected. A cartridge gas energized bolt carrier assembly is moveable within the upper receiver and is provided with anti-tilt guidance with respect to a spring energized buffer mechanism, that is provided within a butt-stock of the lower receiver. The bolt carrier assembly moves a cartridge from a magazine and feeds the cartridge into the cartridge chamber of the barrel and returns the bolt carrier assembly to its closed and locked condition upon dissipation of the cartridge gas energizing force. The bolt carrier assembly is efficiently guided to prevent its misalignment during its rearward and forward auto-loading movement.

Abstract: To permit ease and efficiency for the extraction of spent cartridge cases from the cartridge chamber of a firearm barrel within a wide range of temperature conditions, the internal tapered surface of the body region of a cartridge chamber is prepared by establishing circumferentially spaced longitudinal straight or curved regions of the internal surface finish to create an internal cartridge chamber geometry having gradually tapered spaced longitudinally relieved linear or spiral areas having longitudinal linear or spiral lands between each of the relieved areas. The circumferentially spaced lands develop controlled impedance to rearward cartridge case movement on cartridge firing to effectively protect the bolt and extractor mechanisms of the firearm against early failure.

Abstract: A tactical firearm has an upper receiver defining a handguard mounting surface oriented in substantially normal relation with the bore of a rifle barrel and defining handguard mounting flanges that project radially from the upper receiver. A handguard is provided with like radiating handguard mounting flanges and is releasably secured to the upper receiver by fasteners. A barrel extends through the handguard and is secured by a barrel retainer to the upper receiver in a manner achieving clearance and thermal isolation of the handguard from the barrel and barrel retainer.

Abstract: A free-standing post supported target mechanism has a support post of a defined cross-sectional geometry. A baseplate defines a post opening receiving the support post and has a first orientation permitting movement of the baseplate along the length of the support post and a second orientation establishing a gripping relation with the support post. A spall plate defines a post opening receiving the support post and has a first orientation permitting movement of the spall plate along the length of the support post and a second orientation establishing a gripping relation of the spall plate with the support post. A target plate engages the baseplate and the spall plate and is secured by a locking member. A target base defines a receptacle receiving and supporting the support post and establishes a weight-forward condition that offsets the rearward forces of bullet impact.

Abstract: A suppressor mechanism has an elongate tubular housing containing baffles and into which is assembled a suppressor mount body having spaced thread sections and spaced tapered gas seal surfaces. An adapter/muzzle brake member defines an internally threaded section that establishes threaded connection with the reduced diameter externally threaded section of a typical firearm barrel that is prepared for attachment of a suppressor thereto. The suppressor mount body and the muzzle brake/adapter member each define spaced threaded sections that establish threaded connection and promote enhanced structural integrity. The spaced internal tapered surfaces of the suppressor mount body and the spaced external tapered surfaces of the muzzle brake/adapter member establish spaced internal cartridge gas seals that prevent high pressure hot cartridge gas and gunpowder residue from coming into contact with and potentially fouling the thread connections of the suppressor mount body and the muzzle brake/adapter member.

Abstract: A pivot mount base is assembled to or removed from the sight mounting rail of a firearm by a lever actuated cam energized rail clamping mechanism. A pivot shaft is fixed within an axially oriented pivot passage of the mount base and defines spaced external bearing surfaces. A pivotal accessory support device defines spaced pivot receptacles having a portion of said pivot mount base located therebetween and has bearing receptacles receiving the pivot shaft. The accessory support device is moveable both linearly and rotatably relative to the fixed pivot shaft and is urged toward a locked position with a locking pin by a compression spring and is moved against the spring force to free the accessory support device for manual rotational movement to a precision aiming position and to a laterally offset position.

Abstract: A free-standing post supported target mechanism has a support post of a defined cross-sectional geometry. A baseplate defines a post opening receiving the support post and has a first orientation permitting movement of the baseplate along the length of the support post and a second orientation establishing a gripping relation with the support post. A spall plate defines a post opening receiving the support post and has a first orientation permitting movement of the spall plate along the length of the support post and a second orientation establishing a gripping relation of the spall plate with the support post. A target plate engages the baseplate and the spall plate and is secured by a locking member. A target base defines a receptacle receiving and supporting the support post and establishes a weight-forward condition that offsets the rearward forces of bullet impact.

Abstract: A firearm has a receiver extension defining a plurality of spaced butt-stock positioning receptacles. A butt-stock has a locking pin that is moveable into one of the receptacles for locking the butt-stock at a desired position on the receiver extension. A lock pin actuator is manually moveable by applying a force to a pull ring member to cause retraction of the locking pin from a butt-stock positioning receptacle in preparation for position adjustment or removal of the butt-stock relative to the receiver extension. A rotary knob lock positioning member is rotatable to locked and unlocked positions and when locked ensures against complete separation of the butt-stock from the receiver extension member upon maximum length adjustment of the butt-stock.

Abstract: A sight mount for firearms having short sight mount blocks and having sheet metal receiver covers. A mount base is pivotally connected with the sight mount block and has a sight support platform that is positioned above the receiver cover and provides support for an optical sighting device. A lock member has releasable locking engagement with the lock retainer members and having a portion thereof engaging the rear sight block and securing said mount base against movement from said sighting position. A rear sight member is defined by an upturned portion of the lock member and has a sighting notch that is visible in co-witnessing relation when viewing through the optical sighting device.

Abstract: A cartridge gas port selector mechanism for a firearm barrel having a plurality of gas ports extending from the barrel bore and having a gas block with gas passages in communication with a gas tube. A selector valve member is movable within the gas block between an open condition permitting flow of cartridge gas from one or more ports of the firearm barrel to the cartridge gas passage and a closed condition blocking flow of cartridge gas from the barrel bore to the cartridge gas passage. A valve selector or actuator is connected with the valve member and is selectively moveable to position the valve member at the open condition or the closed condition to select the volume and timing of cartridge gas communication from the barrel bore to the gas energized autoloading mechanism of the firearm.

Abstract: A pivot mount base is assembled to or removed from the sight mounting rail of a firearm by a lever actuated cam energized rail clamping mechanism. A pivot shaft is fixed within an axially oriented pivot passage of the mount base and defines spaced external bearing surfaces. A pivotal accessory support device defines spaced pivot receptacles having a portion of said pivot mount base located therebetween and has bearing receptacles receiving the pivot shaft. The accessory support device is moveable both linearly and rotatably relative to the fixed pivot shaft and is urged toward a locked position with a locking pin by a compression spring and is moved against the spring force to free the accessory support device for manual rotational movement to a precision aiming position and to a laterally offset position.

Abstract: A method for and apparatus absorbing the energy of a projectile strike by a multiplicity of energy dissipating elements of high mass that are contained within a spaced defined by walls. A projectile passing through one of the walls transmits its energy to a multiplicity of energy dissipating elements, such as hardened steel balls or various shaped objects of high mass, by causing energy transfer and distribution through a loose mass of the energy dissipating elements and disintegrating the projectiles. Energy absorbing apparatus embodying this method may take the form of a static or moveable bullet or projectile trap, an energy absorbing external barrier or shelter on vehicles, and portable personnel protection structures for use in a tactical environment. The energy absorbing and dissipating elements are subject to some movement in response to the energy imparted by the projectiles and quickly settle after the energy has been dissipated.