| Platform | Mk3 |
| Caliber | 8.6 BLK |
| Operating System | Compact Action-Direct Impingement |
| Barrel Length | 12.5 |
| Barrel Twist | 1:3 |
| Barrel Contour | MT |
| Barrel Material | 4140CM, Nitride Finish |
| Barrel Twist | 1:3 |
| Muzzle Device | CMMG ZEROED Linear Compensator |
| Muzzle Thread | 5/8 x 24 |
| Gas Port Location | Pistol |
| Gas Block | Adjustable 0.750" |
| Upper Receiver | DISSENT Mk3 7075 T6 Alumunium |
| Hand Guard | CMMG 11" Proprietary |
| Finish | Cerakote or Hard Coat Anodized |
| Charging Handle | Dissent Side Charger - Reversible |
| Receiver Extension | 1913 Picatinny Rail End Cap |
| Weight | 5.5 lbs |
Expected to ship within 15-30 business days.
State/local restrictions may apply. Please review our Firearms Shipping Policy prior to ordering.
Upper Group, DISSENT, Mk3, 8.6 BLK, 12.5"
Are you wanting to build a DISSENT® Mk3 with the highly anticipated 8.6 caliber? The cartridge is unique for its radical 1:3 twist rate which produces extreme rotational energy. The design allows for shorter barrels and subsonic ammunition to be used.
Pair with a compatible lower receiver and the included 1913 Picatinny rear end plate you can add accessories like slings if you're going for a pistol build or a folding stock if a compact carbine is more your style.
Utilizing our patent pending direct impingement Compact Action, DISSENT upper groups house the entire action and recoil assembly in the upper receiver resulting in less bulk and length than traditional ARs. The forward non-reciprocating side charger allows for quick bolt operation without coming off target.
All DISSENT Upper groups include a 1913 Picatinny rail end plate to use in place of the lower receiver buffer tube. Upper groups are available in your choice from seven Cerakote finish options.
Adjustable Gas Block
If you’re looking to shoot suppressed or just fine tune your DISSENT to your preferred ammo, the adjustable gas block gives you the freedom to dial in the gas system exactly to your liking. Never too much and never too little.
Lifetime Quality Guarantee
We aim to please, that’s why every CMMG product is backed by our Lifetime Quality Guarantee against material and workmanship defects. Learn More.
Mk3 DISSENT upper groups are designed to work with CMMG Mk3 (DPMS LR308 Gen-1 Pattern) lower receivers. Due to design differences, other manufacturers’ LR308 lowers may work but CMMG can only guarantee proper fit and function with Mk3 lower receivers.