A bolt catch device is disclosed. The bolt catch includes a movable surface configured to be positioned within a weapon so as to conditionally engage a bolt so as to prevent the bolt from rechambering a next round from a magazine, a tip configured to, in response to a received force, cause the movable surface to move so as to release the bolt, and a spring engagement feature configured to be positioned within the weapon so as to receive a spring within the weapon, wherein the spring within the weapon is configured to bias the movable surface toward a position which prevents the bolt from rechambering a next round.

Provided is a last round bolt hold-open mechanism for a firearm with a removable ammunition magazine and a longitudinally reciprocating bolt that automatically releases the bolt when a loaded ammunition magazine is inserted. The mechanism includes a frame mountable to a firearm receiver and having a pair of mounting flanges. A catch member is pivotally mounted on a pivot axle oriented transverse to the longitudinal reciprocation of the bolt and carried by the mounting flanges. The catch member has a rearward portion that moves between bolt blocking and bolt release positions and is spring biased toward the bolt blocking position. A forwardly extending finger is configured to be lifted by the presence of at least one ammunition cartridge in the magazine and, when lifted, causes the catch member to pivot to the bolt release position.

A reciprocating bolt assembly has delayed blowback and a firing pin block. Features prevent out-of-battery firing, when the bolt assembly is not fully engaged to the firing chamber or barrel face, a movable member within a bolt body functions as a blocking member that blocks the firing pin and prevents the firing pin from striking a cartridge. In embodiments, the firing pin has two stop portions that the movable member can engage depending on the cycle status of the firearm. A reverse cam mechanism associated with the firing pin blocking provides a resistance to and delays blowback.

A reciprocating bolt assembly has delayed blowback and a firing pin block. Features prevent out-of-battery firing, when the bolt assembly is not fully engaged to the firing chamber or barrel face, a movable member within a bolt body functions as a blocking member that blocks the firing pin and prevents the firing pin from striking a cartridge. In embodiments, the firing pin has two stop portions that the movable member can engage depending on the cycle status of the firearm. A reverse cam mechanism associated with the firing pin blocking provides a resistance to and delays blowback.

A bolt assembly has a rear block configured for connection at the rear end of the bolt passage, a bolt carrier configured to reciprocate in the bolt passage, a support element between the rear block and the bolt carrier, a first spring between the support element and the rear block, the bolt carrier defining a bore, the support element including a guide rod slidably received in the bore, and a second spring encompassing the guide rod, having a rear end abutting the support element, and a forward portion received in the bore. The bolt carrier may include a bolt carrier body, and the bolt carrier may include a weight portion movably connected to the bolt carrier body. The weight portion may define a through hole receiving an intermediate portion of the guide rod and an intermediate portion of the second spring.

A bolt assembly has a rear block configured for connection at the rear end of the bolt passage, a bolt carrier configured to reciprocate in the bolt passage, a support element between the rear block and the bolt carrier, a first spring between the support element and the rear block, the bolt carrier defining a bore, the support element including a guide rod slidably received in the bore, and a second spring encompassing the guide rod, having a rear end abutting the support element, and a forward portion received in the bore. The bolt carrier may include a bolt carrier body, and the bolt carrier may include a weight portion movably connected to the bolt carrier body. The weight portion may define a through hole receiving an intermediate portion of the guide rod and an intermediate portion of the second spring.

A firearm reliability system may include a charging handle insert and a variable bolt weight assembly. Other components of a firearm reliability system may include, but are not limited to, a buffer pressure plug, extractor springs, firing pin springs, one or more firing pins, and bolt buffers. The firearm reliability system may address weaknesses in the common rimfire AR bolt system. Using the firearm reliability system, malfunctions may be essentially eliminated. Each component of the firearm reliability system plays a part and interfaces with the others (i.e., the bolt weight spreads the impact on the buffer into a larger area, while reducing the speed at which the bolt impacts the backplate, which then reduces the energy transferred to the buffer pressure plug and thus the impact with the lower receiver).

A firearm reliability system may include a charging handle insert and a variable bolt weight assembly. Other components of a firearm reliability system may include, but are not limited to, a buffer pressure plug, extractor springs, firing pin springs, one or more firing pins, and bolt buffers. The firearm reliability system may address weaknesses in the common rimfire AR bolt system. Using the firearm reliability system, malfunctions may be essentially eliminated. Each component of the firearm reliability system plays a part and interfaces with the others (i.e., the bolt weight spreads the impact on the buffer into a larger area, while reducing the speed at which the bolt impacts the backplate, which then reduces the energy transferred to the buffer pressure plug and thus the impact with the lower receiver).

A firearm mount, components thereof, and associated methods. The firearm can be configured for use with an AR-15 style firearm or other type of firearm. The firearm mount is adapted to securely hold the firearm assembly in position for cleaning, maintenance, and/or gunsmithing tasks. The firearm mount can include a lock configured to selectively lock and unlock a firearm assembly thereon.

A firearm mount, components thereof, and associated methods. The firearm can be configured for use with an AR-15 style firearm or other type of firearm. The firearm mount is adapted to securely hold the firearm assembly in position for cleaning, maintenance, and/or gunsmithing tasks. The firearm mount can include a lock configured to selectively lock and unlock a firearm assembly thereon.