Abstract: A gas operated system for use in semiautomatic firearms is disclosed. The gas operated system utilizes a gas powered assembly which is actuated by gas under pressure. The gas powered assembly is utilized to provide rearward motion to a drive assembly. The drive assembly has a rod associated therewith which engages unlocking structure so that this structure unlocks locking structure so that the bolt assembly can move rearwardly from the battery position. Movement of the bolt assembly rearwardly is accomplished principally due to expanding gas present in the barrel of the firearm which acts against the face of the bolt assembly.