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.