A universal chassis for a firearm includes sidewalls. The sidewalls define a trigger well that is configured to receive a trigger mechanism. One of the sidewalls may define a cutout adjacent the trigger well. The chassis is configured to interchangeably receive a bolt action and a barrel for a shotgun, a muzzle loader, and a rifle. The cutout is sized and dimensioned to receive a lever arm of the bolt action.

A universal chassis for a firearm includes sidewalls. The sidewalls define a trigger well that is configured to receive a trigger mechanism. One of the sidewalls may define a cutout adjacent the trigger well. The chassis is configured to interchangeably receive a bolt action and a barrel for a shotgun, a muzzle loader, and a rifle. The cutout is sized and dimensioned to receive a lever arm of the bolt action.

An interchangeable barrel assembly for a firearm including a novel barrel and tool assembly which are used with a receiver having an open aft end. The tool assembly is configured to be inserted into the receiver open aft end so as to engage the aft end of the barrel. Torque applied to the tool assembly thereby transfers torque to the barrel without transferring forces to the action. This enables the same action to be used with different barrels and the barrel may be removed without removing the receiver or other components of the modular chassis or accessories mounted thereon. Additionally, standard torque may be applied to the barrel for connection to the receiver and firearm precision is maintained.

An automatic weapon arranged according to the bullpup scheme and containing a barrel; a receiver in the form of a cylinder rolling in a rectangular box; a mechanism for moving the shell from the magazine into the chamber, being a part of the chamber, designed in the form of a drum, its feature is an open chamber where bullets come out of the store vertically; a trigger mechanism comprising a piston rod of the gas tube, which is a drummer; an axis of the drum; a shutter; shock and amortization springs; a frame hook of the rod over the escapement; a trigger pivotally mounted on the frame axis, travelling through the cylindrical receiver grooves horizontally, connected with a fork by a drum; a venting mechanism with a gas tube and a piston; a return mechanism; a multifunction ammunition cartridge of extended capacity, feeding bullets into the machine vertically.

An automatic weapon arranged according to the bullpup scheme and containing a barrel; a receiver in the form of a cylinder rolling in a rectangular box; a mechanism for moving the shell from the magazine into the chamber, being a part of the chamber, designed in the form of a drum, its feature is an open chamber where bullets come out of the store vertically; a trigger mechanism comprising a piston rod of the gas tube, which is a drummer; an axis of the drum; a shutter; shock and amortization springs; a frame hook of the rod over the escapement; a trigger pivotally mounted on the frame axis, travelling through the cylindrical receiver grooves horizontally, connected with a fork by a drum; a venting mechanism with a gas tube and a piston; a return mechanism; a multifunction ammunition cartridge of extended capacity, feeding bullets into the machine vertically.

Disclosed is an autoloading shotgun firearm which shares interchangeable fully compatible modular sub-assemblies, ergonomics, parts commonality, and exterior appearance with the AR rifle platform. Rapidly reversible tool less conversion from rifle to shotgun and vice versa is accomplished by substitution of the AR rifle upper receiver and ammunition detachable magazine with fully compatible shotgun upper receiver and ammunition detachable magazine. Said shotgun utilizes standard rimmed shotgun ammunition via features in the detachable magazine which securely maintain the position and facilitate the feeding of the cartridges during normal operation. No alteration of the AR rifle lower receiver is required. A short-recoil action is integrated into the shotgun upper receiver. The external appearance and functionality of the AR rifle are retained while eliminating the complexity and inherent fouling issues of typical gas systems used in the AR rifle. A short-recoil action also enables the shotgun to function reliably with shorter length barrels.

Disclosed is an autoloading shotgun firearm which shares interchangeable fully compatible modular sub-assemblies, ergonomics, parts commonality, and exterior appearance with the AR rifle platform. Rapidly reversible tool less conversion from rifle to shotgun and vice versa is accomplished by substitution of the AR rifle upper receiver and ammunition detachable magazine with fully compatible shotgun upper receiver and ammunition detachable magazine. Said shotgun utilizes standard rimmed shotgun ammunition via features in the detachable magazine which securely maintain the position and facilitate the feeding of the cartridges during normal operation. No alteration of the AR rifle lower receiver is required. A short-recoil action is integrated into the shotgun upper receiver. The external appearance and functionality of the AR rifle are retained while eliminating the complexity and inherent fouling issues of typical gas systems used in the AR rifle. A short-recoil action also enables the shotgun to function reliably with shorter length barrels.

A firearm barrel configured to attach to a muzzle device including a muzzle device bore and a tapered interior surface tapering from a first, wider portion at a proximal end of the muzzle device to a second, narrower portion away from the proximal end. The firearm barrel includes a barrel bore, a first, proximal end, a second, distal end, and a tapered exterior surface tapering from a first, wider portion to a second, narrower portion towards the distal end of the barrel, wherein the tapered exterior surface is configured to operably mate with the tapered interior surface of the muzzle device to optimize axial alignment of the barrel bore with the muzzle device bore.

Implementations of the present disclosure relate to apparatuses, systems, and methods for constructing, installing, and using a compression follower in a tubular firearm magazine. In particular, the compression follower resides inside a shotgun magazine and replaces the standard follower. The compression follower has a compressible tail, thereby providing the capacity of a standard follower and increased reliability by aligning the follower and a magazine spring.

An improved trigger assembly for a firearm includes twin disconnectors that are each independently selectable and adjustable to provide different trigger pull weights. The trigger assembly may be operably controlled by the safety selector which defines several different shaped engaging surfaces that allow the operator to selectively choose which of the disconnectors to operate with the firearm.