Retaining devices securable on firearms are selectively operable to engage and retain a bolt assembly in a substantially-fixed position for an indeterminate period of time. The retaining devices include a mounting plate securable to the receiver and a retention pin that extends through a passage in the mounting plate. The retention pin extends axially between first and second ends that project outwardly beyond the mounting plate. The retention pin is supported on the mounting plate for axial displacement between a first pin position and a second pin position. In the first pin position, the second end of the retention pin engages and retains the bolt assembly in a substantially-fixed position relative to the receiver. In the second pin position, the second end of the retention pin is disengaged from the bolt assembly.

A selective fire firearm may be provided having a fully automatic open bolt and a semi-automatic closed bolt mode of operation. The firearm may include a trigger group having a trigger prop that ensures that, when the trigger is released in the fully automatic open bolt mode, the bolt carrier stops in an open bolt position held by an open bolt sear. The trigger prop may include a foot that, following a first trigger pull in the fully automatic open bolt mode, slides under and props a rear end of the trigger in a position that allows the open bolt sear to catch the bolt carrier when the trigger is released and propped but prevents the trigger sear from engaging the hammer.

A selective fire firearm may be provided having a fully automatic open bolt and a semi-automatic closed bolt mode of operation. The firearm may include a trigger group having a trigger prop that ensures that, when the trigger is released in the fully automatic open bolt mode, the bolt carrier stops in an open bolt position held by an open bolt sear. The trigger prop may include a foot that, following a first trigger pull in the fully automatic open bolt mode, slides under and props a rear end of the trigger in a position that allows the open bolt sear to catch the bolt carrier when the trigger is released and propped but prevents the trigger sear from engaging the hammer.

The present invention relates to a firearm shooting with an open breech and comprising a detent mechanism with a hammer block (5) that can block the forward movement of movable parts (2), a trigger (10) that can lift the hammer block (5) when the movable parts (2) move backwards, an action bar (12) that actuates the hammer block (5) and the trigger (10) when shooting is triggered and stopped, and a finger piece (13) linked to the action bar (12) by a disconnector (11) that can shift from a position in which the finger piece (13) is mechanically coupled to the action bar (12) to a position in which the finger piece (13) is mechanically uncoupled from the action bar (12), the action bar (12) shifting from a shooting position to a rest position when the disconnector (11) shifts from its coupling position to its uncoupling position so as to prevent the following shot from being fired if the finger piece (13) is maintained in the shooting position.

The invention relates to mechanisms for cocking an automatic weapon. An automatic firearm having an inertial automation system comprises a breech, a barrel, a bolt support with a bolt, a recoil spring and a return spring, a trigger mechanism, an ammunition supply mechanism and a bolt support latch. The latch fixes the bolt support in a rear position and is controlled with a trigger. A shot is produced at the instant the bolt support arrives in a front position. A mechanism for supplying cartridges to a cartridge chamber makes it possible to load the weapon when the bolt support is fixed in the rear position. Stable operation of an inertial automation system is achieved.

The invention relates to mechanisms for cocking an automatic weapon. An automatic firearm having an inertial automation system comprises a breech, a barrel, a bolt support with a bolt, a recoil spring and a return spring, a trigger mechanism, an ammunition supply mechanism and a bolt support latch. The latch fixes the bolt support in a rear position and is controlled with a trigger. A shot is produced at the instant the bolt support arrives in a front position. A mechanism for supplying cartridges to a cartridge chamber makes it possible to load the weapon when the bolt support is fixed in the rear position. Stable operation of an inertial automation system is achieved.

A firearm includes a barrel having a breech end and a vent path through the barrel downstream from the breech end. A receiver is engaged with the breach end of the barrel and defines a chamber. A latch is connected to the receiver, and an actuator is downstream from the vent path and operably engaged with the latch. A bolt is at least partially inside the chamber. The bolt has a locked position in which the latch is engaged with the bolt to prevent the bolt from moving away from the breech end of that barrel and a released position in which the latch is not engaged with the bolt.

The disclosed embodiments are directed to enhancing insensitive munitions performance. Some of the embodiments employ an outgassing pad having unique geometrical configurations, compositions, and positioning. Other embodiments rely on using thermally-releasable components to foster billet expulsion. Additional embodiments combine both aspects into entire cook-off mitigation systems for insensitive munitions improvements.

The disclosed embodiments are directed to enhancing insensitive munitions performance. Some of the embodiments employ an outgassing pad having unique geometrical configurations, compositions, and positioning. Other embodiments rely on using thermally-releasable components to foster billet expulsion. Additional embodiments combine both aspects into entire cook-off mitigation systems for insensitive munitions improvements.

The disclosed embodiments are directed to enhancing insensitive munitions performance. Some of the embodiments employ an outgassing pad having unique geometrical configurations, compositions, and positioning. Other embodiments rely on using thermally-releasable components to foster billet expulsion. Additional embodiments combine both aspects into entire cook-off mitigation systems for insensitive munitions improvements.