SIG MCX .300 Blackout assault rifle Default

SIG MCX .300 Blackout assault rifle Default (MCX .300 BLK Default)

The .300 Blackout MCX line, designed and manufactured by SIG Sauer, is available in both semi-automatic and automatic versions and features a short-stroke gas piston system, which is inherited from the earlier SIG MPX submachine gun. The .300 Blackout ammo and the MCX are compatible with all AR-15 magazines.