A rifle having a straight pull bolt assembly with a bolt handle that extends outward and downward from a bolt operation mechanism. The bolt handle rotatable a limited rotational range forward and rearwardly about a horizontal axis for operating the mechanism. The handle can be reconfigured to position its rotational range about the horizontal axis and can be attached to the mechanism at either left or right sides to provide for ambidextrous operation. Bolt heads, lower frame members with magazine wells, and barrel assemblies can be readily swapped to change ammunition. The bolt assembly can be unlocked by firing or by a thumb push button release at the backside of the mechanism. A bolt removal release mechanism is forward of the thumb pushbutton and an ejector includes a spring bias and cam follower surface to reliably eject casings.

A semiautomatic or fully automatic firearm that includes a barrel, the rear barrel end whereof is in the form of a cartridge chamber into which a cartridge can be inserted, a breech body which is arranged such that it can move in the longitudinal direction between an open position, which releases the cartridge chamber for the reloading of a cartridge, and a closed position which closes the cartridge chamber, wherein the breech body closes the cartridge chamber at the rear in the closed position and is used as a support for the cartridge case of the cartridge, wherein the firearm has a mass simulation body which is in force-fitting engagement with the breech body, in particular a mass simulation body which is rigidly connected to the breech body, the mass simulation body being formed at least in part from a magnetizable or a magnetic material.

A semiautomatic or fully automatic firearm that includes a barrel, the rear barrel end whereof is in the form of a cartridge chamber into which a cartridge can be inserted, a breech body which is arranged such that it can move in the longitudinal direction between an open position, which releases the cartridge chamber for the reloading of a cartridge, and a closed position which closes the cartridge chamber, wherein the breech body closes the cartridge chamber at the rear in the closed position and is used as a support for the cartridge case of the cartridge, wherein the firearm has a mass simulation body which is in force-fitting engagement with the breech body, in particular a mass simulation body which is rigidly connected to the breech body, the mass simulation body being formed at least in part from a magnetizable or a magnetic material.

A suppressed pistol has a breech block and a slide mounted on a frame. The breech block and slide are separate pieces, movable relatively to one another and the frame. A link extends between the breech block and the frame. The link carries a cam and a cam follower. The cam follower on the link engages a cam on the frame, the cam on the link engages a cam follower on the slide. Action between the cams, cam followers and the link causes separation between the breech block and the slide during operation of the pistol. The suppressor includes a container having baffle plates with truncated cones defining openings offset from the geometric centers of the baffle plates.

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.

An operating system for a firearm includes a forward bolt includes a forward bolt cavity, a carrier disposed on a rear side of the forward bolt, the carrier including a carrier cavity, a short cam pin including (i) a forward section that is at least partially disposed within the forward bolt cavity and (ii) a rear section that is at least partially disposed within the carrier cavity, a plurality of bearings that interface with the forward bolt, a retracted configuration where the short cam pin is in a rear position relative to the forward bolt, and a deployed configuration where the short cam pin is in a forward position relative to the forward bolt.

An operating system for a firearm includes a forward bolt includes a forward bolt cavity, a carrier disposed on a rear side of the forward bolt, the carrier including a carrier cavity, a short cam pin including (i) a forward section that is at least partially disposed within the forward bolt cavity and (ii) a rear section that is at least partially disposed within the carrier cavity, a plurality of bearings that interface with the forward bolt, a retracted configuration where the short cam pin is in a rear position relative to the forward bolt, and a deployed configuration where the short cam pin is in a forward position relative to the forward bolt.

An automatic firearm breech mechanism is provided that ensures that the delaying roller remains an integral part of the breech mechanism after removing the breech mechanism from the firearm. The automatic firearm breech mechanism may include a breech, a breech carrier, and a delaying roller that is positioned between a rear vertical wall of the breech and a front vertical wall of the breech carrier. The delaying roller may move vertically while between the rear vertical wall of the breech and the front vertical wall of the breech carrier. A modified cage may surround the working area of the delaying roller. The cage may be a strip bent into the shape of an inverted letter U, featuring an opening located on its horizontal wall, while its vertical walls are fitted with a slide stop at both ends.

A bolt carrier speed control apparatus that is configured to provide adjustable speed control of the bolt carrier during firing of a round of ammunition. The bolt carrier speed control apparatus is configured to be mounted in a first location or a second location. The bolt carrier speed control apparatus includes a body that is cylindrical in form. The body includes and interior volume and further includes a central bore extending longitudinally therethrough. Circumferentially disposed around the central core are a plurality of movement assemblies. The movement assemblies are configured to move in an inward-outward direction that is facilitated by traversal of an adjustment screw through the central bore. The movement assemblies include a wall engagement member that is configured to extend beyond the external surface of the body so as to engage a portion of the firearm and provide speed control of the bolt carrier through added friction.