Abstract: A firearm may have gas operating system that renders the firearm capable of firing a wide range of shot loads by passively or automatically compensating for different shot loads. The firearm may include a plurality of ports formed in the firearm barrel, and corresponding ports formed in a gas block of the gas operating system. The ports tap gases generated during firing which are used to cycle the firearm. When firing different cartridge loads, differing combinations of the ports are selectively at least partially blocked or otherwise obstructed by the cartridge casing according to the size of the cartridge. Additionally, the gas operating system includes compensating gas pistons with internal relief valves that can bleed off excess gas to compensate for larger shot loads regardless of the size of the cartridge.

Abstract: A firearm may have gas operating system that renders the firearm capable of firing a wide range of shot loads by passively or automatically compensating for different shot loads. The firearm may include a plurality of ports formed in the firearm barrel, and corresponding ports formed in a gas block of the gas operating system. The ports tap gases generated during firing which are used to cycle the firearm. When firing different cartridge loads, differing combinations of the ports are selectively at least partially blocked or otherwise obstructed by the cartridge casing according to the size of the cartridge. Additionally, the gas operating system includes compensating gas pistons with internal relief valves that can bleed off excess gas to compensate for larger shot loads regardless of the size of the cartridge.

Abstract: A gas operating system for a firearm renders the firearm capable of firing a wide range of shot loads by passively or automatically compensating for different shot loads. The firearm includes a plurality of ports formed in the firearm barrel, and corresponding ports formed in a gas block of the gas operating system. The ports tap gases generated during firing which are used to cycle the firearm. When firing different cartridge loads, differing combinations of the ports are selectively at least partially blocked or otherwise obstructed by the cartridge casing according to the size of the cartridge. Additionally, the gas operating system includes compensating gas pistons with internal relief valves that can bleed off excess gas to compensate for larger shot loads regardless of the size of the cartridge.

Abstract: A gas operating system for a firearm renders the firearm capable of firing a wide range of shot loads by passively or automatically compensating for different shot loads. The firearm includes a plurality of ports formed in the firearm barrel, and corresponding ports formed in a gas block of the gas operating system. The ports tap gases generated during firing which are used to cycle the firearm. When firing different cartridge loads, differing combinations of the ports are selectively at least partially blocked or otherwise obstructed by the cartridge casing according to the size of the cartridge. Additionally, the gas operating system includes compensating gas pistons with internal relief valves that can bleed off excess gas to compensate for larger shot loads regardless of the size of the cartridge.

Abstract: A gas operating system for a firearm renders the firearm capable of firing a wide range of shot loads by passively or automatically compensating for different shot loads. The firearm includes a plurality of ports formed in the firearm barrel, and corresponding ports formed in a gas block of the gas operating system. The ports tap gases generated during firing which are used to cycle the firearm. When firing different cartridge loads, differing combinations of the ports are selectively at least partially blocked or otherwise obstructed by the cartridge casing according to the size of the cartridge. Additionally, the gas operating system includes compensating gas pistons with internal relief valves that can bleed off excess gas to compensate for larger shot loads regardless of the size of the cartridge.

Abstract: A magazine cutoff device for a firearm with a tube-type magazine, such as, e.g., semi-automatic shotgun. The cutoff device may be moveably mounted to accommodate at least two positions, on and off. The user may activate the cutoff, pull the bolt to the rear, eject a chambered shell, and lock the bolt to the rear while retaining any shells in the magazine.

Abstract: A magazine cutoff device for a firearm with a tube-type magazine, such as, e.g., semi-automatic shotgun. The cutoff device may be moveably mounted to accommodate at least two positions, on and off. The user may activate the cutoff, pull the bolt to the rear, eject a chambered shell, and lock the bolt to the rear while retaining any shells in the magazine.