The multi-barrel split-breech rapid fire gun is a light-weight, electrically-driven rapid fire gun, radially loaded and fired, using only rotating parts. This eliminates inertia problems compared to a breech-loaded gun that requires a bolt to chamber a cartridge. The firing mechanism allows the cartridge to be enclosed in a split-breech for 50% one rotation of the barrel hub. The gun incorporates an independent firing pin for each barrel to allow for high firing rates. The gun is fed by a thin polyimide cartridge belt fan-folded in a detachable wet-magazine.

An upper receiver for a firearm. The firearm includes a barrel extending forward of the upper receiver and a buttstock extending rearward of the upper receiver. The upper receiver includes an arcuate surface formed in a wall of the chamber. The arcuate surface changes direction of gases that are directed rearward in the chamber such that the gases are vented from the upper receiver in a non-rearward direction.

An upper receiver for a firearm. The firearm includes a barrel extending forward of the upper receiver and a buttstock extending rearward of the upper receiver. The upper receiver includes an arcuate surface formed in a wall of the chamber. The arcuate surface changes direction of gases that are directed rearward in the chamber such that the gases are vented from the upper receiver in a non-rearward direction.

The multi-barrel split-breech rapid fire gun is a light-weight, electrically-driven rapid fire gun, radially loaded and fired, using only rotating parts. This eliminates inertia problems compared to a breech-loaded gun that requires a bolt to chamber a cartridge. The firing mechanism allows the cartridge to be enclosed in a split-breech for 50% one rotation of the barrel hub. The gun incorporates an independent firing pin for each barrel to allow for high firing rates. The gun is fed by a thin polyimide cartridge belt fan-folded in a detachable wet-magazine.

An upper receiver for a firearm. The firearm includes a barrel extending forward of the upper receiver and a buttstock extending rearward of the upper receiver. The upper receiver includes an arcuate surface formed in a wall of the chamber. The arcuate surface changes direction of gases that are directed rearward in the chamber such that the gases are vented from the upper receiver in a non-rearward direction.

An upper receiver for a firearm. The firearm includes a barrel extending forward of the upper receiver and a buttstock extending rearward of the upper receiver. The upper receiver includes an arcuate surface formed in a wall of the chamber. The arcuate surface changes direction of gases that are directed rearward in the chamber such that the gases are vented from the upper receiver in a non-rearward direction.

The present invention relates to a self-powered device for measuring a firing rate, comprising: a) a thermoelectric generator (2) that converts thermal energy into electrical energy; b) a system (3) that is able to determine the temperature of the barrel (7); c) a system for processing and recording said measurements (4); d) characterized in that the system for determining temperature (3) and the system for processing and recording measurements (4) are powered by the thermoelectric generator (2).

Air as conventionally known is comprised of about 78% nitrogen and 21% oxygen with other trace gases such as carbon dioxide, neon, and hydrogen. Other gases (e.g. helium) and partial vacuums have both a lower density and a higher speed-of-sound from that of conventional air or even some highly utilized propellant gases. The present application and described embodiments take advantage of these principles to provide a purge gas mixture and system to increase the speed of a projectile exiting the muzzle-end of a gun barrel. A partial vacuum may also be used in certain applications.

Air as conventionally known is comprised of about 78% nitrogen and 21% oxygen with other trace gases such as carbon dioxide, neon, and hydrogen. Other gases (e.g. helium) and partial vacuums have both a lower density and a higher speed-of-sound from that of conventional air or even some highly utilized propellant gases. The present application and described embodiments take advantage of these principles to provide a purge gas mixture and system to increase the speed of a projectile exiting the muzzle-end of a gun barrel. A partial vacuum may also be used in certain applications.

A system, device, and method for measuring the temperature of a chambered projectile within a firearm are provided. A test ammunition round may include a projectile, a sleeve, and a case including a first end coupled to sleeve, and a second end coupled to the projectile. A thermocouple may be located within the projectile, and an electronic coupler may be coupled to the thermocouple, and extends through the case and the sleeve and exits the sleeve through a slot for coupling to a data acquisition system.