FUN FACT! CHAMBER MUST LINE UP WITH BARREL & CHAMBER SHOULD USE AMMUNITION THAT IS NOT MUCH LARGER THAN THE BARREL! GAS TUBE AND BOLT CARRIER WITH PISTON OF RIFLE (TOTALLY UNNECESSARY); RIFLE BARREL (7.62MM); CHAMBER OF PISTOL, 9MM; WHEN VIDEO GAME DEVS DON'T KNOW ANYTHING AT ALL ABOUT GUNS