CMMG Dissent MK4 30B0E67AB | .300 AAC Blackout | 6.50 in

The CMMG Dissent MK4 upper group is a compact AR-platform upper built around CMMG’s Compact Action and radial delayed blowback system. It is configured for .300 AAC Blackout and fitted with a short 6.50 in barrel and a left-side, non-reciprocating charging handle for off-hand operation. The Dissent design houses the action and recoil assembly in the upper receiver, reducing overall length compared with traditional AR pistol assemblies. This configuration is aimed at users building AR-platform pistols or short-barrel AR builds who want a compact, integrated upper group.

Product Specifications

• The manufacturer is CMMG.
• The model is Dissent MK4.
• The manufacturer part number is 30B0E67AB.
• The caliber is .300 AAC Blackout.
• The barrel measures 6.50 inches.
• The barrel finish is Black.
• The rate of twist is 1:10.
• The handguard type is 4.60 in M-LOK.
• The handguard finish is Armor Black.
• The overall finish of the upper is Armor Black.
• The charging handle is left-side non-reciprocating.
• The muzzle device is a zeroed linear compensator.
• The upper includes a Picatinny end plate for use in place of a lower receiver buffer tube.
• This upper is designed to fit AR-platform lowers and builds.
• The UPC is 810097509207.

The Dissent MK4 upper packages the action and recoil assembly into a compact, ready-to-install unit that simplifies short-barrel AR builds and pistol configurations. Its combination of a short, black-finished barrel, left-side charging handle and M-LOK handguard makes it practical for confined-range training and short-range precision or suppressed shooting setups.