Abstract: An extractor/ejector system is described for automatically extracting a cartridge from the breech of a firearm or automatically ejecting the cartridge when the cartridge has been fired. A gas port is provided in the barrel of the arm to direct gases from the barrel against a piston: a piston rod connected to the piston contacts a sear and is forced into a latched position with an extractor/ejector spring in compressed condition. When the action of the firearm is broken, a lug is provided for contacting an extractor having a camming surface contacting the sear. The motion of the extractor caused by the lug forces the sear out of engagement, permitting the ejector spring to rapidly expend and effectively eject the fired cartridge.