Firearms employing gas pressure loading mechanisms are disclosed. An example firearm includes a single force receiving component containing a gas cylinder, and a barrel in communication with a cartridge chamber received in the force receiving component. The cartridge chamber is in communication with a gas withdrawal-opening and is sized to fire cartridges having a caliber of at least 15 mm. The firearm also includes a bore in communication with the gas withdrawal opening and the gas cylinder. Fu...

A gas-power system for an autoloading shotgun in which a pair of gas cylinders are mounted on opposite sides of and between the barrel and the magazine tube. An inertial weight is slidably mounted on the magazine for engagement by the pistons, which are positively retained within their cylinders for limited movement when a shell is discharged. The inertial weight is connected to the bolt-mechanism by a pair of action bars.

A gas operated semi-automatic rifle is disclosed having a forwardly moving gas piston located under the discharge end of a barrel. The gas piston is connected to a locking mechanism. The locking mechanism is engaged with a breechblock. As the gas piston moves a short distance forward after a round has been fired from the rifle, the locking mechanism moves rearward and disengages from the breechblock. The breechblock is biased rearward by being disengaged from the locking mechanism. The breechblo...

An operating system for automatic rifles is described which permits a user to easily remove and replace the bolt and bolt carrier from the rifle, without requiring the user to employ special tools. This invention permits the user to reconfigure the rifle to fire a wide range of different calibers of cartridges, as well as to reconfigure the rifle to feed ammunition from either the top or the bottom of the firearm. This invention further improves the reliability and decreases the manufacturing co...

A weapon system is disclose whose design permits simple reconfiguration of the weapon to perform optimally in many configurations. By reconfigurations, the weapon can be configured to fire a wide variety of cartridges, including but not limited to 7.62.times.39 mm, 5.45.times.39 mm, 5.56 NATO, 0.45 ACP, 9 mm, 40 S&W, and 0.300 Magnum. This reconfiguration is accomplished by easily changing the following components: barrel; operating rod, recoil spring, and buffer; gas tube, bolt head, firing pin...

An apparatus adapted for actuating a bolt carrier group apparatus comprising a piston tube attached to a receiver assembly. An operating rod is disposed in a bore of the piston tube. A piston is engaged with a first end of the operating rod. The operating rod moves from a static position to a displaced position when a combustion gas is exposed to a face of the piston. A bolt carrier including a bolt carrier lug is disposed in a bolt carrier lug channel of an upper receiver body. A tappet rod is ...

An improved gas locked firearm using expanding gases to force a bullet through a barrel in which a portion of said gases are diverted through a gas port communicating with a gas locking chamber adjacent said barrel which chamber is formed between said barrel and an extension arm of the bolt or breech block extending forward therefrom a distance along the rear portion of the barrel and forming an elongated gas chamber between a shoulder on the rear of the barrel and a plate extending from said br...

A gun comprising a frame, a barrel, and a slide. The barrel and the slide being slidably mounted to one another and to the frame for movement between a retracted position and an extended position; the barrel having a bore and having a gas port communicating with the bore for allowing gas to pass from the bore when the gun is fired; the gun having a chamber communicating with the gas port when the barrel and slide are in the retracted position and for receiving gas from the gas port when the gun ...

A spirally-wound, formed pin used as an orifice liner in a gas operated firearm. The spirally-wound, hollow, spring steel pin is useful in locating the gas cylinder on the barrel for the brazing operation and improves the location accuracy of the gas cylinder due to spring pin expansion. The spring pin tends to act as a protective liner to lessen the erosive effects of the explosive gases on the braze joint connecting the gas cylinder to the barrel.

Firearms having a locked breech are disclosed. An example firearm includes a barrel; a bolt head; a firing pin having a bulge; a bolt head carrier having a forward position and a rearward position; a central force receiving component receiving a rear end of the barrel and defining a plurality of recesses; and a locking bolt penetrating the bolt head. The locking bolt is movable between: (1) a locked position wherein the locking bolt engages in the recesses of the central force receiving componen...