The CMMG Dissent Mk3 8.6 Blackout AR Pistol (brand part no. 33A9E0C-CT) brings CMMG’s larger-caliber companion to the .300 Blackout onto the AR10-sized Dissent Mk3 platform, pairing a 12.5-inch barrel with the heavier, harder-hitting .338-caliber projectiles that 8.6 Blackout is built around. CMMG finishes the receiver in Coyote Tan Cerakote and equips it with an M-LOK handguard, a rear Picatinny rail, and the company’s ambidextrous ZEROED controls, giving shooters a compact big-bore AR pistol that runs the way a full-size Dissent does. The barrel’s incredibly fast 1:3 twist rate is tuned specifically for 8.6 Blackout’s heavy bullets, letting the round perform out of a short barrel and suppress just as effectively as .300 Blackout despite the larger case. Among our AR pistols, the Dissent Mk3 8.6 Blackout suits shooters who want more power on target than .300 Blackout delivers, in a platform built for short-barrel and suppressed use.

Key Specifications

• The chambering is 8.6 Blackout.
• The barrel is 12.5 inches long and threaded.
• The barrel finish is black nitride.
• The rate of twist is an incredibly fast 1:3 inches, tuned for 8.6 Blackout’s heavy .338-caliber bullets.
• The magazine capacity is 20+1 rounds.
• The receiver is Coyote Tan Cerakote aluminum with a Picatinny rail.
• The handguard is an M-LOK handguard.
• A rear Picatinny rail is included for accessories.
• The grip is a CMMG ZEROED pistol grip.
• The safety is a CMMG ZEROED 60/90-degree ambidextrous selector.

Frequently Asked Questions

Is 8.6 Blackout the same as .300 Blackout? No. 8.6 Blackout is CMMG’s larger-caliber companion round, built on the same short-barrel, suppressor-friendly design philosophy as .300 Blackout but firing heavier .338-caliber projectiles on the AR10-sized Dissent Mk3 platform.

Why does the barrel use such a fast twist rate? The 1:3 twist is tuned specifically to stabilize 8.6 Blackout’s heavy bullets, letting the cartridge perform out of a short barrel the way it’s designed to.

Does it run well suppressed? Yes, CMMG built 8.6 Blackout to suppress as effectively as .300 Blackout despite firing a larger, heavier projectile.

Buy the CMMG Dissent Mk3 8.6 Blackout AR Pistol

A genuinely bigger-hitting alternative to .300 Blackout in a compact, suppressor-friendly AR pistol, the Dissent Mk3 8.6 Blackout gives serious shooters more downrange power without giving up the platform’s short-barrel handling. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL.