Gas tube assembles are provided for mounting on a gas block of a gas-actuated firearm having an internal passage configured to receive propellant gas from a barrel of the firearm. The gas tube assemblies have a gas tube that defines a passage extending between a forward and a rearward end of the gas tube. The gas tube assemblies also have a mating portion secured to the gas tube. The mating portion has a flange that can be secured to the gas block so that the flange prevents linear and rotational movement of the gas tube in relation to the gas block.

A gas piston assembly comprises a piston apparatus having a first end and a second end. A piston bonnet has a bonnet end wall with a bonnet aperture defined therethrough and a bonnet sidewall to receive the second end of the piston apparatus therein. A piston gap is between the second end of the piston apparatus and the bonnet end wall and communicates with the bonnet aperture. An adjustable gas regulator communicates with the bonnet aperture and selectively occludes the bonnet aperture in fully open, partially open and fully closed orientations. The bonnet end wall includes a threaded bore in communication with the bonnet aperture. The gas regulator includes a threaded shaft received within the threaded bore which translates to selectively occlude the bonnet aperture. The threaded shaft includes a head portion gripped by a user while a detent engages a recess on a bottom face of the head portion.

A gas piston assembly comprises a piston apparatus having a first end and a second end. A piston bonnet has a bonnet end wall with a bonnet aperture defined therethrough and a bonnet sidewall to receive the second end of the piston apparatus therein. A piston gap is between the second end of the piston apparatus and the bonnet end wall and communicates with the bonnet aperture. An adjustable gas regulator communicates with the bonnet aperture and selectively occludes the bonnet aperture in fully open, partially open and fully closed orientations. The bonnet end wall includes a threaded bore in communication with the bonnet aperture. The gas regulator includes a threaded shaft received within the threaded bore which translates to selectively occlude the bonnet aperture. The threaded shaft includes a head portion gripped by a user while a detent engages a recess on a bottom face of the head portion.

Example apparatus are disclosed for a gas feed for an automatic firearm, the gas feed comprising a mounting portion to fasten the gas feed on a firearm barrel, the gas feed comprising a gas cylinder connectable to a barrel bore inside the firearm barrel via a gas channel, a gas piston disposed inside the gas cylinder to drive a gas operated reloading mechanism, wherein the gas piston is displaceable in a longitudinal direction with respect to the firearm, and a closure element that can be detachably coupled to an end of the gas cylinder adjacent a stock of the firearm, wherein the closure element comprises a passage through which a gas piston can be disposed.

Example apparatus are disclosed for a gas feed for an automatic firearm, the gas feed comprising a mounting portion to fasten the gas feed on a firearm barrel, the gas feed comprising a gas cylinder connectable to a barrel bore inside the firearm barrel via a gas channel, a gas piston disposed inside the gas cylinder to drive a gas operated reloading mechanism, wherein the gas piston is displaceable in a longitudinal direction with respect to the firearm, and a closure element that can be detachably coupled to an end of the gas cylinder adjacent a stock of the firearm, wherein the closure element comprises a passage through which a gas piston can be disposed.

An adjustable gas block, including at least some of a body portion with a barrel borehole extending therethrough; a gas block extension portion extending from the body portion; a gas tube borehole extending through the gas block portion and into at least a portion of the gas block extension portion; a gas block gas port in fluid communication between the barrel borehole and the gas tube borehole; a vent aperture extending through the gas tube borehole, providing fluid communication between the gas tube borehole and an exterior of the gas block extension portion; and a vent cap rotatably positionable relative to the gas block extension portion so as to be positioned between a closed position, wherein the vent cap obstructs, blocks, or occludes the vent aperture, and an open position, wherein the vent cap does not obscure, block, or occlude the vent aperture.

An adjustable gas block, including at least some of a body portion with a barrel borehole extending therethrough; a gas block extension portion extending from the body portion; a gas tube borehole extending through the gas block portion and into at least a portion of the gas block extension portion; a gas block gas port in fluid communication between the barrel borehole and the gas tube borehole; a vent aperture extending through the gas tube borehole, providing fluid communication between the gas tube borehole and an exterior of the gas block extension portion; and a vent cap rotatably positionable relative to the gas block extension portion so as to be positioned between a closed position, wherein the vent cap obstructs, blocks, or occludes the vent aperture, and an open position, wherein the vent cap does not obscure, block, or occlude the vent aperture.

A system for an adjustable gas block. The gas block body has a main chamber fluidly coupled to a gas aperture which is fluidly connected to a plunger channel and a gas return path. Downstream of the gas block body is a plunger assembly which includes a ring and a plunger. Further downstream is an adjustment knob which is coupled to the gas block body and which is adjustable upstream and downstream relative to the gas block body. The volume of plunger inserted into the channel path is controlled by the adjustment knob.

A system for an adjustable gas block. The gas block body has a main chamber fluidly coupled to a gas aperture which is fluidly connected to a plunger channel and a gas return path. Downstream of the gas block body is a plunger assembly which includes a ring and a plunger. Further downstream is an adjustment knob which is coupled to the gas block body and which is adjustable upstream and downstream relative to the gas block body. The volume of plunger inserted into the channel path is controlled by the adjustment knob.

A bullpup rifle, which has models existing in the art operating individually in pump-action, semi-automatic and automatic systems in the defense industry and the hunting weapon sector, having a barrel, in which the ammunition/cartridge are fired, the barrel having at least one gas discharge hole. A gas system is provided to convert the semi-automatic and automatic rifles to manual (pump-action) and/or pump-action system of the rifle to semi-automatic and automatic system, through opening and closing the gas discharge hole feeding the gas chamber on the barrel by clockwise and/or counterclockwise movement of the gas chamber located on and surrounding the barrel, allowing automatic and/or semi-automatic shooting in the open position of the gas discharge hole and manual (pump-action) shooting in the closed position.