The PWS MK109 MOD 2-M .300 Blackout SBR is a short-barreled rifle built around a 9.75-inch 41V50 barrel with a 1:6 twist. It operates on the PWS Long Stroke Piston System, which Primary Weapons Systems builds for reliability and reduced fouling, with a 3-setting adjustable gas system tuned for suppressor use. The receivers are forged aluminum with an ambidextrous lower, and the PicLok handguard combines Picatinny and M-LOK mounting. PWS finishes the rifle with Magpul MOE SL stock and MOE K2 grip. It suits a shooter who wants a compact .300 Blackout rifle that stays comfortable behind a suppressor.

Key Specifications

• The chambering is .300 Blackout, a cartridge built for short barrels and subsonic loads.
• Barrel length is 9.75 inches in 41V50 steel, which keeps the rifle compact.
• Twist rate is 1:6, suited to heavier subsonic .300 Blackout bullets.
• The gas system is the PWS Long Stroke Piston with a 3-setting adjustable gas system, which reduces fouling and lets you tune it for suppressed use.
• The furniture is a Magpul MOE SL stock and MOE K2 pistol grip, which come standard on the rifle.

Frequently Asked Questions

What handguard does the MK109 use? It uses the PWS PicLok handguard, which combines Picatinny and M-LOK mounting for accessories.

Do I need ATF approval to buy this? No. As of October 9, 2026, ATF no longer requires Form 4 approval, registration or a tax stamp for short-barreled rifles. It transfers on a Form 4473 with a background check through a Class 3 (SOT) dealer. State and local laws still apply. Taking an SBR across state lines still requires an approved ATF Form 5320.20.

Buy the PWS MK109 MOD 2-M .300 Blackout SBR, 9.75-Inch Barrel

As of October 9, 2026, this short-barreled rifle transfers on a Form 4473 with a background check at your Class 3 (SOT) dealer, with no Form 4 or tax stamp; state and local laws still apply. The piston system and adjustable gas make it a low-fouling choice for suppressed .300 Blackout shooting. Order through PWS‘s short-barreled rifles lineup and our Lubbock, Texas team will handle the transfer, and it ships fast to your Class 3 dealer.