Springfield M1A SOCOM, Semi-automatic, 308 Win, 16.25 Barrel, Black Finish, Synthetic Stock, Adjustable Sights, 10Rd AA9626 The M1A(TM) Socom 16 starts with a specially-engineered 16 inch barrel that is mated to the gas system with a proprietary muzzle brake. Shoot the M1A(TM) SOCOM 16 and you'll be double-checking the stamping on the barrel, because you'll have a hard time believing that you're shooting a .308.