An attachable extension can be attached to a firearm adjustment knob comprising an extension rod and a mounting block wherein the extension rod can slide back and forth axially and rotatably within the mounting block. A knob mounted to the extension rod and a spring mounted around the extension rod for biasing the extension rod toward a gas exhaust knob, and a fastener capturing the mounting block to a barrel shroud wherein the knob movably rotates the extension rod axially within the mounting block. The extension rod further comprises a slot fitted over gas exhaust knob. The extension rod can be coupled to the knob by a pin.

An attachable extension can be attached to a firearm adjustment knob comprising an extension rod and a mounting block wherein the extension rod can slide back and forth axially and rotatably within the mounting block. A knob mounted to the extension rod and a spring mounted around the extension rod for biasing the extension rod toward a gas exhaust knob, and a fastener capturing the mounting block to a barrel shroud wherein the knob movably rotates the extension rod axially within the mounting block. The extension rod further comprises a slot fitted over gas exhaust knob. The extension rod can be coupled to the knob by a pin.

A gas block assembly may include a gas block including a gas port to receive gas provided by a gas port of a barrel; a tapered fastener opening; and a tapered fastener insertable in the tapered fastener opening, the tapered fastener including: a length further including a tapered section to contact a sidewall that defines the tapered fastener opening; and means for rotationally driving the tapered fastener into the tapered fastener opening. In other embodiments, an adjustable gas block includes sealing ring(s) on a groove in a rotationally actuated gas metering shaft.

A gas block assembly may include a gas block including a gas port to receive gas provided by a gas port of a barrel; a tapered fastener opening; and a tapered fastener insertable in the tapered fastener opening, the tapered fastener including: a length further including a tapered section to contact a sidewall that defines the tapered fastener opening; and means for rotationally driving the tapered fastener into the tapered fastener opening. In other embodiments, an adjustable gas block includes sealing ring(s) on a groove in a rotationally actuated gas metering shaft.

The present invention relates to a pressure control structure that is developed to be used in semi-automatic firearms operating with gas pressure, that allows for using any type of live ammunition (small/magnum) easily by maintaining the stability of the gas pressure created as a result of firing the firearm and enables cocking the rifle mechanism, that protects the parts of the rifle as well as the assembly thereof and that provides the user a more comfortable firing experience.

The present invention relates to a pressure control structure that is developed to be used in semi-automatic firearms operating with gas pressure, that allows for using any type of live ammunition (small/magnum) easily by maintaining the stability of the gas pressure created as a result of firing the firearm and enables cocking the rifle mechanism, that protects the parts of the rifle as well as the assembly thereof and that provides the user a more comfortable firing experience.

A firearm including a barrel, receiver, indirect gas system and an adjustable gas block designed to interface with the indirect gas system is provided. Four indexable positions of adjustment are provided for on the adjustable gas block. Positions of adjustment are selected based on the use of a silencer, use of under-powered ammunition, the presence of un-burnt powder and debris in the host firearms operating system, or if the weapon is being fired under “ideal” circumstances. The provided gas block is designed to function with an indirect gas operating system. Excess gas from the operating system is not vented from the gas block thereby generating excess flash and sound. No tool is required to manipulate the adjustment mechanism of the gas.

A firearm including a barrel, receiver, indirect gas system and an adjustable gas block designed to interface with the indirect gas system is provided. Four indexable positions of adjustment are provided for on the adjustable gas block. Positions of adjustment are selected based on the use of a silencer, use of under-powered ammunition, the presence of un-burnt powder and debris in the host firearms operating system, or if the weapon is being fired under “ideal” circumstances. The provided gas block is designed to function with an indirect gas operating system. Excess gas from the operating system is not vented from the gas block thereby generating excess flash and sound. No tool is required to manipulate the adjustment mechanism of the gas.

Systems and methods for an adjustable gas block are described. Systems may include an adjustment subassembly. The adjustment subassembly may include a valve stem end with a front-most portion larger in diameter than the rear-most portion and a boss extending from the forward portion of the valve stem end; a valve ring surrounding the boss of the valve stem end; a valve threaded portion for receiving the boss of the valve stem end and having a threaded portion; and a valve rotator coupled to the valve threaded portion for adjusting the flow of gas. Systems may include a gas block assembly. The gas block assembly may include a gas block through hole; a first duct to direct pressurized gas from a barrel to a plenum; a second duct to direct a regulated volume of gas to a gas operating system; a seat valve to control the regulated volume of gas to the gas operating system; and a gas block threaded portion for coupling to the valve threaded portion. The adjustment subassembly may be coupled to the gas block assembly.

Systems and methods for an adjustable gas block are described. Systems may include an adjustment subassembly. The adjustment subassembly may include a valve stem end with a front-most portion larger in diameter than the rear-most portion and a boss extending from the forward portion of the valve stem end; a valve ring surrounding the boss of the valve stem end; a valve threaded portion for receiving the boss of the valve stem end and having a threaded portion; and a valve rotator coupled to the valve threaded portion for adjusting the flow of gas. Systems may include a gas block assembly. The gas block assembly may include a gas block through hole; a first duct to direct pressurized gas from a barrel to a plenum; a second duct to direct a regulated volume of gas to a gas operating system; a seat valve to control the regulated volume of gas to the gas operating system; and a gas block threaded portion for coupling to the valve threaded portion. The adjustment subassembly may be coupled to the gas block assembly.