Cmmg Dissent 30A650A-Ab Br4 300Bo 16.1 *Ca Armbk

The CMMG Dissent BR4 300 Blackout carbine is a modern, do-it-all platform built around one of the most versatile cartridges in use today. Whether you're running subsonic rounds through a suppressor for stealth, pushing supersonic loads for hunting, or putting rounds downrange at the range, this 16.1-inch rifle is engineered to adapt to your mission. The Dissent line is CMMG's answer to shooters who want a purpose-built 300 BLK platform that doesn't sacrifice ergonomics, modularity, or shootability.

Built on CMMG's proprietary BR4 billet receiver set machined from 7075 T6 aluminum, the Dissent combines a direct impingement operating system with a carbine-length gas system tuned for reliable function across the subsonic-to-supersonic spectrum. The 16.1-inch barrel features a 1:7 twist rate optimized for the full range of 300 BLK projectiles, and it's crowned with a CMMG ZEROED muzzle brake (5/8-24 threads) that helps manage recoil and improves handling. A full-length Picatinny rail on top gives you mounting flexibility for any optic or sighting system, while the 15-inch M-LOK handguard provides ample real estate for accessories and a modern ergonomic grip.

The Dissent side-charging handle keeps the receiver profile clean and offers left and right operation, and the reversible safety selector accommodates both right and left-handed shooters. Trigger duty falls to a CMMG ZEROED drop-in single-stage unit—crisp and predictable out of the box. Two 10-round Magpul PMags, an adjustable gas block for tuning, and a Magpul SGA stock complete the package. Finished in Cerakote and tipping the scales at 7.8 pounds, this is a rifle that feels as good as it shoots.

Key Features

• 300 Blackout caliber: optimized for both subsonic and supersonic ammunition
• 16.1-inch barrel with 1:7 twist rate for versatile bullet performance
• Direct impingement with carbine-length gas system and adjustable gas block
• Full-length top Picatinny rail for optic mounting and accessory mounting
• 15-inch M-LOK handguard for modularity and ergonomic control
• CMMG ZEROED muzzle brake (5/8-24 threads) to manage recoil
• Side-charging handle with reversible operation
• Reversible cross-bolt safety for ambidextrous use
• CMMG ZEROED drop-in single-stage trigger
• Magpul SGA stock and two 10-round PMAG magazines included
• 7075 T6 aluminum receiver set for strength and light weight
• Cerakote finish for durability

Specifications

Frequently Asked Questions

What ammunition does the CMMG Dissent BR4 300 Blackout shoot?

This rifle is chambered in .300 Blackout and designed to run both subsonic (typically 220 grains and slower) and supersonic (125–150 grain) loads reliably. The 1:7 barrel twist and adjustable gas block allow you to tune performance across the cartridge's range—critical when you're mixing ammunition types.

Can I suppress this rifle?

Yes. The CMMG Dissent features a 5/8-24 threaded muzzle and a carbine-length gas system, both of which support suppressor use. The adjustable gas block lets you dial in performance with a suppressor installed, especially with subsonic ammunition. A muzzle brake is installed; you can replace it with a suppressor adapter if needed.

What's included with this rifle?

The Dissent comes with two Magpul 10-round PMags, a Magpul SGA stock, and is ready to mount an optic on the full-length Picatinny rail. The CMMG ZEROED trigger and muzzle brake are installed.

Is this rifle ambidextrous?

The side-charging handle and reversible safety selector both accommodate left and right-handed shooters, making the Dissent suitable for either hand.