The building block gun is an American engineer Ogen who shocked the gun industry. Tim. Developed in stoner, caliber 5. 56 mm, its basic common components are bolt, case, recoil spring, launching mechanism, etc. And 65,438+06 special or partial parts such as gun barrels, gun butts and sights, which can be combined into six kinds of guns, including automatic rifles, submachine guns, magazine-fed light machine guns, chain-fed machine guns, vehicle-mounted machine guns and medium-sized machine guns with tripods.