Abstract: An adjustable volume gas piston system for a pneumatic reloading firearm includes a gas block having an anchoring portion for anchoring along the barrel. The gas block also includes a chamber portion in pneumatic connection with the barrel. The chamber portion has one end pointing toward the muzzle and another end pointing away from the muzzle. A plug having a bore is affixed to the chamber portion at the forward end. The second end has an opening to allow travel of a gas pin but retains a gas pin head in the chamber portion, biasing it toward the first end. Upon firing the firearm, the volume of the bore causes a pressure delay on the gas pin head, thereby delaying the timing of pneumatic reloading.

Abstract: An adjustable firearm gas block has a gas channel intersected by a threaded bore. A set screw with longitudinal slots is driven through the bore until it enters and constricts the gas channel. A second bore, parallel to the first bore, is connected to the first bore by a passage. A spring and a detent plunger having a slanted notch are inserted in the second bore with a bearing located in the slanted notch and passage. When the detent plunger is in a resting position, it presses the bearing into a longitudinal slot, preventing the set screw from turning. When the detent plunger is urged away from the resting position, the bearing disengages the longitudinal slot, traveling into the slanted notch and allowing the set screw to rotate, thereby adjusting the gas pressure emitted by the gas block.

Abstract: An adjustable firearm gas block has a gas channel intersected by a threaded bore. A set screw with longitudinal slots is driven through the bore until it enters and constricts the gas channel. A second bore, parallel to the first bore, is connected to the first bore by a passage. A spring and a detent plunger having a slanted notch are inserted in the second bore with a bearing located in the slanted notch and passage. When the detent plunger is in a resting position, it presses the bearing into a longitudinal slot, preventing the set screw from turning. When the detent plunger is urged away from the resting position, the bearing disengages the longitudinal slot, traveling into the slanted notch and allowing the set screw to rotate, thereby adjusting the gas pressure emitted by the gas block.