Embodiments of the present disclosure provide modifications to the AR platform operating system such that the platform now is competent to fire large caliber cartridges, including belted cartridges, providing longer range and greater barrier penetration without substantially altering the characteristic features and component inter-relationships of this platform.

Embodiments of the present disclosure provide modifications to the AR platform operating system such that the platform now is competent to fire large caliber cartridges, including belted cartridges, providing longer range and greater barrier penetration without substantially altering the characteristic features and component inter-relationships of this platform.

A firearm having a lower receiver including a takedown pin through hole and an upper receiver configured to receive the lower receiver. The upper receiver including a rear lug and the rear lug including a bore and a screw disposed in the bore. A takedown pin having a cam surface such that the upper receiver is drawn to the lower receiver as the takedown pin is inserted in the takedown pin through hole and the bore of the rear lug.

Devices, systems, and methods of manufacturing are disclosed with regard to a rapid-fire accessory that mounts onto a semi-automatic firearm using structural features thereof and/or added thereon to guide a trigger actuator for engaging a trigger and repeatedly firing the semi-automatic firearm. The rapid-fire accessory does not require the removal or replacement of the original, replacement, or aftermarket firearm grip or most other components of the firearm. The rapid-fire accessory provides a structural component an operator may hold that facilitates bump firing the semi-automatic firearm. Once mounted on the semi-automatic firearm, the rapid-fire accessory may slide rearward and forward, using a bottom rail on or below a forend of the semi-automatic firearm as a guiding surface and securing element. The rapid-fire accessory also includes a forward-hand grip for comfortably and securely holding the rapid-fire accessory steady, while the semi-automatic firearm is pushed forward and then recoils backward from discharging.

Disclosed is a lower receiver that defines an aperture extending between a bolt stop well and an actuator well, the lower receiver including a bolts stop and a first actuator lever on one side of the lower receiver and a bolt stop actuator that includes a tooth that extends through the aperture, a second bolt release lever on the other side of the lower receiver and a rod connecting the tooth and the second bolt release lever, wherein the tooth engages the bolt stop so that actuation of the second bolt release lever moves the bolt stop and where the first and second release levers move in unison.

A bolt carrier for a firearm, including lugs on the first end to engage corresponding lugs of a barrel receiver/extension. The bolt carrier includes a cam slot within which a cam pin from a bolt is constrained to travel along a cam slot path during rotational and translational movement of the bolt. The cam slot defines (1) a first cam slot means for constraining motion of the cam pin and the bolt during engagement or disengagement of the lugs of the bolt and the corresponding lugs of the barrel receiver or extension; (2) a second cam slot means for imparting rotational movement to the cam pin and bolt during linear movement of the bolt carrier; and (3) a third cam slot means for constraining motion of the cam pin at an end of a rearward travel of the bolt and bolt carrier during an ejection cycle. The combination of the first, second, and third cam slot means yields an extension of the unlocking by over 10% and a delay of the actual unlock of the bolt by over 5% relative to TDP.

A captive recoil spring assembly includes a guide rod surrounded by a coil spring. The spring is captured between a base at one end of the guide rod, and a body at its opposite end. The body is shaped to engage the spring at one or more sectors, leaving one or more remaining sectors free to engage the slide. Use of such a body permits a round wire spring to be used without the need for close dimensional tolerances on the engaging parts.

The present disclosure presents a barrel assembly for a firearm. The barrel assembly includes a barrel having an internal bore and an external surface, and a recoil spring lug affixed to an outside surface of the barrel. The barrel assembly also includes a slide moveably mounted relative to the barrel, and a recoil spring biased on the recoil spring lug and the slide.

A firearm includes a receiver for housing a trigger mechanism. The receiver is attached to a firearm barrel, and the receiver includes a bolt carrier that is configured to reciprocate therein. The firearm includes a recoil spring that has a first end and a second end, and the first end interfaces with the bolt carrier. The recoil spring further includes a dampened portion positioned between the first and second ends. The dampened portion has a plurality of dead spring coils. The firearm also includes a spring retainer that is configured to retain the recoil spring within the firearm.

An insert for repair or increase durability of 1911-style firearms is disclosed. In addition, a grip modification particularly suited for concealed carry is disclosed.