MasterPiece Arms is releasing a new SBR: the MPA570SST-SBR. The 570SST-SBR will be chambered in 5.72 x 28, have adjustable front and rear sights, side-cocking charging handle, muzzle brake, MPA’s own short aluminum quadrail, a low profile folding buttstock and the Strike Industries Foregrip. The Barrel will be 10″ threaded, featuring 1/2″ x 28 threads so it will be ‘can-ready’. The MPA 570SST-SBR is based on their MPA57SST 5.72 x 28 MM pistol.
About the stock:

The MPA stock works with 930, 30, 10 or 57 series pistol receivers. It secures to the frame w/ ¼-20 threaded hole behind grip on the lower section receiver. Features a lock nut to hold the screw in place on the inside of the receiver below the sear plate.
MPA570SST-SBR
Side Cocker, Scope Mount
one (1) 8″ Threaded Barrel
one (1) 20 Round Polymer Magazine
one (1) Muzzle Brake
Thread Size 1/2 x 28
American Made
Ships in Gun Case
Lifetime Guarantee
Strike Industries Foregrip
MPA Short Aluminum Quadrail
Adjustable Front Sight
Chamber 5.7x28mm
MPA Low Profile Buttstock
MPA Side Folding Attachment
ALL NFA RULES APPLY
MPA Suppressor Not Included






{ 7 comments… read them below or add one }
Another MAC-10 and no HK MP-7 4.6 caliber …… yawn.
I like to see MP-5 chambered in 4.6mm or 5.7mm or better yet 9×19 worked well for decades. Wish we could get the Russian AP 9x19mm round for PDWs.
What the MP-7 should have been; this could be interesting……
I picked up a MasterPiece Arms 5-7 this weekend and handed it right back to the gun store employee when I felt how HEAVY it was.
In my opinion, nothing beats the P90.
The P90 has a damn fine weapon, but I believe the MP7 is superior.
I agree all elite US units that have used a SMG use now a MP-5 and MP-7 once in a while a M-3.
A full auto GLOCK with a suppresser is a much better choice if you want to jump through the ATF hoops to get it. But a 9mm doesnt getit