CMMG Dissent MK4 .300 AAC Blackout 6.50" Barrel 30-Round Tungsten Gray Cerakote Finish

The CMMG Dissent MK4 .300 AAC Blackout is a compact personal defense rifle that reimagines what an AR-pattern firearm can be. Built around CMMG's patent-pending Compact Action, this 6.50" barrel pistol ditches the traditional buffer tube entirely—the entire recoil system lives in the upper receiver, making the Dissent one of the most genuinely portable AR designs on the market. At 14.7" overall and just 4.8 lbs, it's a serious option for shooters who need serious capability in a seriously small package.

.300 AAC Blackout is the perfect cartridge for a gun like this. It delivers .30 caliber power across a wide range of loadings—hot supersonic rounds for hunting and distance, subsonic ammunition for suppressed work—and the SLR adjustable gas block lets you tune the system to run reliably with whatever you're feeding it. The included TriggerTech AR-D 2-Stage trigger (developed specifically for Dissent platforms) breaks cleanly at 4 lbs and was engineered to optimize this gun's handling. Ambidextrous controls, a non-reciprocating side charger that switches between left and right operation, and a 1913 Picatinny rail for brace or stock attachment round out a feature set built for real shooters, not marketing copy.

The Tungsten Gray Cerakote finish is durable and professional-looking, and the internals—7075 T6 aluminum receivers, 4140CM barrel, CMMG matched components—are built to the quality standard you'd expect from a brand known for American-made precision rifle work. This comes standard with a Magpul 30-round 300BLK PMAG, a CMMG ZEROED linear compensator (5/8 x 24 thread), and everything else you see is integrated into the platform. The Dissent MK4 is a tool for serious shooters who value compactness, modularity, and the freedom to configure their rifle their way.

Key Features

• Patent-pending Compact Action eliminates buffer tube for maximum portability
• 6.50" barrel in .300 AAC Blackout—optimized for both supersonic and subsonic ammunition
• SLR adjustable gas block for fine-tuning to your ammunition type
• TriggerTech AR-D 2-Stage trigger with 4 lb break, developed specifically for DISSENT
• Ambidextrous controls and non-reciprocating side charger (switchable left/right)
• 1913 Picatinny rail end cap for brace or stock attachment
• 4140CM SBR barrel with 1:7 twist rate
• 7075 T6 aluminum forged receivers
• Tungsten Gray Cerakote finish
• Includes Magpul 30-round 300BLK PMAG

Specifications

Frequently Asked Questions

Can I use different triggers in my CMMG Dissent MK4?

The TriggerTech AR-D 2-Stage trigger that comes with your Dissent was developed specifically for this platform to optimize functionality with the Compact Action design. CMMG does not guarantee optimal Dissent functionality with Mil-spec or other aftermarket triggers, so we recommend sticking with the factory-installed trigger or consulting CMMG directly before making substitutions.

Will this work with supersonic and subsonic .300 Blackout ammo?

Yes. The SLR adjustable gas block on this rifle lets you fine-tune the gas system to run reliably with both supersonic and subsonic loadings. This is one of the key advantages of .300 Blackout in a tunable platform like the Dissent—you can dial it in for whatever ammunition type you're running.

Is the side charger ambidextrous?

The DISSENT side charger is non-reciprocating and can be switched between left and right-handed operation, so you can set it up for your preference.

What's included in the box?

The Dissent MK4 comes with a Magpul 30-round 300BLK PMAG and the CMMG ZEROED linear compensator already installed at the muzzle (5/8 x 24 thread). The rifle is ready to shoot once you add a brace or stock to the 1913 Picatinny rail at the rear.