Abstract: A firearm for firing caseless ammunition includes a barrel, a receiver, a bolt, and a firing pin. The bolt includes laterally open pockets for receiving a projectile and a separate propellant cartridge. The bolt carries an extractor to extract unspent projectiles. The bolt drives a locking collar to lock itself in forward position. The locking collar is unlocked by the recoil-action of the firing pin. The firing pin is driven by a spring biased hammer; the firing pin then drives the hammer by recoil action, causing the hammer to unlock the locking collar. A gas seal for the firing pin includes a deformable ring which is deformed by ignition gas pressure into sealing engagement with the firing pin. An anti-recoil muzzle at the discharge end of the barrel has a reaction surface thereof cleaned of combustion deposits by a plurality of bristles extending from the barrel. A propellant cartridge comprises a plurality of telescoping nitrocellulose jackets which form a propellant chamber and a primer compartment.

Abstract: A unitary bolt and chamber adapter for field replacement, without tools, of the conventional bolt assembly of rifles of the type M16 and AR-15 provides for the use of conventional .22 caliber long rifle rimfire ammunition in the rifle instead of the larger conventional centerfire ammunition. The bolt functions in semiautomatic fire by conventional blowback action. Through cooperation with an improved .22 caliber rimfire magazine adapter, the breech automatically remains open after firing the last round from the magazine. The bolt guide rails are flexibly attached to the chamber providing for reliable operation in a larger number of rifles. A spring actuated forward locator on the bolt assembly keeps the adapter seated in the rifle chamber, compensating for differences in gun receiver lengths. An undercut bolt face provides the positive extraction of a double extractor system with a single extractor, and a groove-and-land chamber adapter provides reliable operation with good and poor quality ammunition.

Abstract: An automatic weapon incorporating a retarded blow back, a cartridge and bolt centering assembly, light weight and minimum component construction, simplicity in disassembly, easily detachable barrel, unique belted ammunition feed system, disposable ammunition box, a guide buffering assembly, muzzle brake, remote firing capability, front sight charging system and a bulkhead recoil absorbing arrangement.

Abstract: An automatic weapon with a receiver, a breech block fixedly mounted in the receiver, a barrel reciprocable within the receiver, a spring biasing the barrel, and a gas cylinder chamber externally of the barrel and in communication therewith, whereby upon firing of the weapon, the gases discharged from a cartridge ejected from the barrel, pass into the gas cylinder chamber means to thereby tension the spring.

Abstract: An automatic pistol with blowback action, in which a hammer is cocked by the recoil of a slidable breechblock, has a retaining member in the form of an elongate lid detachably secured to the gunstock for holding the breechblock in place, this lid carrying a backstop for a restoring spring tending to thrust the breechblock forwardly. The rear limiting position of the breechblock is defined by a pair of upstanding wings, rigid with the gunstock, against which two lateral shoulders of the breechblock come to rest upon manual arming or after the firing of a cartridge. A swingable control element on the breechblock, entrainable by a setting knob through a lost-motion coupling, has a blocking position in which it prevents the hammer from striking a firing pin lodged in the breechblock; in a working position, this element is movably interposed between the hammer and the firing pin to act as a force-transmitting device upon the release of the hammer by depression of the trigger.

Abstract: A firearm, comprises a gun housing having a side opening and a gun barrel supported in the housing with a projectile bore which is alignable with a cartridge chamber of a cartridge holder. The cartridge holder is mounted on a bearing member which is journaled in the housing at a position overlying the barrel. A charge handle projects out of the housing and it is guided on the bearing member and is movable relative to the bearing member to cause rotation of the bearing member with the cartridge holder in order to project the cartridge chamber out of the side opening of the housing to a cartridge ejection and loading position. In the cartridge ejection and loading position, an injector pin, which is under the force of a compression spring, is actuated to drive an ejector pin through the chamber and eject any cartridge which may still remain in the chamber as a result of a misfire.

Abstract: A gas-operated, magazine fed firearm includes a shell carrier for receiving shells from the magazine and lifting them into chambering position. An integral shell stop and carrier latch lever pivotally mounted in the receiver latches the shell carrier in its lowered, shell-receiving position and releases a single shell from the magazine to be moved onto the shell carrier by the magazine spring. The shell stop lever blocks the following shell from moving onto the shell carrier and releases the shell carrier for transferring the shell to chambering position. The shell stop lever shifts laterally to permit shells to be loaded past the carrier into the magazine from the feeding end.

Abstract: A combination cartridge extractor-ejector device includes a bolt provided th loop of spring steel having a hook end and a spring end projecting therefrom. When the bolt is moved against the cartridge case in the gun breech, the hook slides over and engages the flanged rim of the case while the spring is compressed against the case end; and when the bolt is moved away from the breech sufficient to extract the engaged case, the spring causes the case to pivot on the hook sufficient to disengage the rim from the hook and thereby eject the case from the gun.

Abstract: A gun bolt is shown which has retractable stop means projecting from the face of the bolt to locate a round of ammunition thereon.

Abstract: Firearm apparatus embodied in a semi-automatic, blowback operated rifle. The firearm includes a receiver made of two plates spaced apart to receive a bolt mechanism including a bolt mounted for reciprocal motion within a channel-shaped member; the operating spring for the bolt assembly is received in a slot within the bolt and is retained in place by the channel-shaped member. A unitary firing pin/extractor carried by the bolt functions as a firing pin and also provides multiple extractor functions. A simplified firing mechanism includes a hammer positioned to the rear of a cartridge magazine and operatively connected by a three-finger sear bar to a trigger mounted in front of the magazine. A safety mechanism is provided in conjunction with the trigger guard. Numerous components of this firearm apparatus provide multiple functions contributing to the economy and efficiency of the present firearm apparatus.