MasterPiece Arms is now making a short barrel rifle (SBR) version of their 5.7×28 gun. Â The new SBR has a threaded 8″ barrel for the included muzzle brake, or for the MPA Suppressor (which is shown in these photos but does not come with the gun). Â Yes, all NFA rules do apply.
The MPA57SST-SBR (aka MasterPiece Arms 5.7×28 SBR) comes outfitted with an MPA short aluminum quadrail and a Strike Industries foregrip.  Based on the photos, the foregrip appears to be the “Cobra Tactical” that normally retails for $25.