A firearm system is provided. A pump-action firearm, such as a shotgun, includes a buffer attached to a trigger housing. The buffer consists of a resilient or semi-resilient material and is positioned such as to face towards an opening the receiver in which the magazine tube is partially received. The buffer includes a contoured bottom surface and an upper surface, configured in a way which shortens the space available within an opening of a receiver while accommodating the loading of shells into a magazine tube. Upon moving a shell into the opening, such as by pumping the action, the shell impacts the buffer, which stabilizes the shell prior to being lifted by an elevators. For shorter shells, this reduces the risk of a jamming event. For longer shells, the buffer is configured to compress to accommodate the additional length.

A firearm system is provided. A pump-action firearm, such as a shotgun, includes a buffer attached to a trigger housing. The buffer consists of a resilient or semi-resilient material and is positioned such as to face towards an opening the receiver in which the magazine tube is partially received. The buffer includes a contoured bottom surface and an upper surface, configured in a way which shortens the space available within an opening of a receiver while accommodating the loading of shells into a magazine tube. Upon moving a shell into the opening, such as by pumping the action, the shell impacts the buffer, which stabilizes the shell prior to being lifted by an elevators. For shorter shells, this reduces the risk of a jamming event. For longer shells, the buffer is configured to compress to accommodate the additional length.

The present disclosure is directed to firearms that can receive and fire bullets from ammunition with different cartridge case sizes. For example, the receiver may fire a bullet from either a short cartridge, a medium cartridge, or long cartridge after the short, medium, or long cartridge is received by a receiver of the firearm. This firearm may include a receiver portion and a bolt portion that lock together at different relative locations when cartridges of different lengths are received by the receiver portion. The receiver portion may include a first type of alignment retention features (e.g. protrusions) and the bolt portion may include a second type of alignment retention features (e.g. recessions). Once a firearm cartridge is located inside of the firearm, it may be fired based on the receiver and the bolt portions being locked together via physical engagement of the different types of alignment retention features.

The present invention provides a chambering device for a barrel of a gun comprising: a shank extending longitudinally between a front end and a rear end and having a plurality of cutting flutes disposed between the front end and the rear end; a shaft extending to the rear end of the shank and adapted to rotate the shank along an interior of the barrel to form a chamber therein, wherein the shank comprises a body region that extends to a shoulder region that transitions to a case mouth that extends to a throat connected to a free bore, wherein the body region comprises a rear diameter near the breech face of about 0.4718; and a body shoulder junction diameter of about 0.4625; wherein the shoulder region comprises a shoulder case mouth junction diameter is between 0.31 to 0.32; a breech face to lead-in bore junction length of between 2.1 to 2.2; a breech face to body-shoulder junction length of between 1.80-1.85; and a breech face to shoulder neck junction length of between 1.9-2.0.

The present invention provides a chambering device for a barrel of a gun comprising: a shank extending longitudinally between a front end and a rear end and having a plurality of cutting flutes disposed between the front end and the rear end; a shaft extending to the rear end of the shank and adapted to rotate the shank along an interior of the barrel to form a chamber therein, wherein the shank comprises a body region that extends to a shoulder region that transitions to a case mouth that extends to a throat connected to a free bore, wherein the body region comprises a rear diameter near the breech face of about 0.4718; and a body shoulder junction diameter of about 0.4625; wherein the shoulder region comprises a shoulder case mouth junction diameter is between 0.31 to 0.32; a breech face to lead-in bore junction length of between 2.1 to 2.2; a breech face to body-shoulder junction length of between 1.80-1.85; and a breech face to shoulder neck junction length of between 1.9-2.0.

A compact firearm has a first frame portion including a barrel defining a barrel axis, a second frame portion including a firing mechanism configured to discharge a cartridge residing in a chamber of the barrel, the second frame portion pivotally connected to the first frame portion to pivot about a pivot axis offset from and parallel to the barrel axis, the first frame portion defining a first mating feature formed as a first surface of revolution about the pivot axis, the second frame portion defining a second mating feature formed as a second surface of revolution about the pivot axis, and the first and second mating features mating closely with each other to prevent relative movement between the first and second frame portions except in relative rotation about the pivot axis. The first and second mating features may be dovetail elements.

A compact firearm has a first frame portion including a barrel defining a barrel axis, a second frame portion including a firing mechanism configured to discharge a cartridge residing in a chamber of the barrel, the second frame portion pivotally connected to the first frame portion to pivot about a pivot axis offset from and parallel to the barrel axis, the first frame portion defining a first mating feature formed as a first surface of revolution about the pivot axis, the second frame portion defining a second mating feature formed as a second surface of revolution about the pivot axis, and the first and second mating features mating closely with each other to prevent relative movement between the first and second frame portions except in relative rotation about the pivot axis. The first and second mating features may be dovetail elements.

A compact firearm has a frame including a barrel defining a chamber, the frame being movable between a closed condition in which the firearm is operable to discharge a cartridge in the chamber, and an open condition in which the chamber is open for loading, a latch movable between a latched condition to retain the frame in the closed condition, and an unlatched condition to enable movement of the frame to the open condition, a firing mechanism connected to the frame and operable in response to actuation to discharge the cartridge in the chamber, and a trigger element operably connected to the firing mechanism to selectably actuate the firing mechanism, and operably connected to the latch to move the latch to the unlatched condition. The trigger element may be operable to selectably actuate the firing mechanism in response to movement in a first direction.

A compact firearm has a frame including a barrel defining a chamber, the frame being movable between a closed condition in which the firearm is operable to discharge a cartridge in the chamber, and an open condition in which the chamber is open for loading, a latch movable between a latched condition to retain the frame in the closed condition, and an unlatched condition to enable movement of the frame to the open condition, a firing mechanism connected to the frame and operable in response to actuation to discharge the cartridge in the chamber, and a trigger element operably connected to the firing mechanism to selectably actuate the firing mechanism, and operably connected to the latch to move the latch to the unlatched condition. The trigger element may be operable to selectably actuate the firing mechanism in response to movement in a first direction.

A compact firearm has a frame including a barrel defining a chamber, the frame being movable between a closed condition in which the firearm is operable to discharge a cartridge in the chamber, and an open condition in which the chamber is open for loading, a latch movable between a latched condition to retain the frame in the closed condition, and an unlatched condition to enable movement of the frame to the open condition, a firing mechanism connected to the frame and operable in response to actuation to discharge the cartridge in the chamber, and a trigger element operably connected to the firing mechanism to selectably actuate the firing mechanism, and operably connected to the latch to move the latch to the unlatched condition. The trigger element may be operable to selectably actuate the firing mechanism in response to movement in a first direction.