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will this work with a Aero precision M5 lower ?

Yes. In fact, I tried one with mine and the colors are an exact match.

by Eric McInnis, Verified Owner, December 28, 2025

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Product Info for CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver

With a barrel length of 20in this 6.5 Creedmoor DISSENT Mk3 Upper Group balances maneuverability with the performance shooters. The CMMG Mk3 platform is based on the popular LR-308/DPMS Gen 1 High-Pattern design. Build from scratch or add to your DISSENT Mk3's caliber possibilities.image

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.

Specifications for CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver:

Manufacturer: CMMG
Caliber: 6.5mm Creedmoor
Barrel Length: 20 in
Barrel Twist Rate: 1-8
Threads per Inch: 5/8x24
Muzzle Device: ZEROED Muzzle Brake
Finish: Cerakote/Hard Coat Anodize
Gun Type: Rifle
Gun Make: CMMG
Gun Model: CMMG Mk3
Weight: 6.6 lb
Condition: New
Barrel Material: 416 Stainless Steel

Features of CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver

  • Adjustable Gas Block
  • Lifetime Quality Guarantee

Package Contents:

  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver

CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver Orderable Models

List of Orderable Models

  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, 65B280C-HCA , MPN: 65B280C-HCA , UPC: 810148628727 , Code: 2CM-URC-CM14UR-65B280C-HCA
  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, Coyote Tan, 65B280C-CT , MPN: 65B280C-CT , UPC: 810148628673 , Code: 2CM-URC-CM14UR-65B280C-CT
  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, Midnight Bronze, 65B280C-MB , MPN: 65B280C-MB , UPC: 810148628680 , Code: 2CM-URC-CM14UR-65B280C-MB
  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, Armor Black, 65B280C-AB , MPN: 65B280C-AB , UPC: 810148628659 , Code: 2CM-URC-CM14UR-65B280C-AB
  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, Tungsten, 65B280C-TNG , MPN: 65B280C-TNG , UPC: 810148628710 , Code: 2CM-URC-CM14UR-65B280C-TNG

CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver Unavailable & Discontinued Models

List of Unorderable Models

  • DEMO, CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, 65B280C-HCA , MPN: 65B280C-HCA-DEMO , Code: 2CM-URC-CM14UR-65B280C-HCA-DEMO
  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, Sniper Grey, 65B280C-SG , MPN: 65B280C-SG , UPC: 810148628697 , Code: 2CM-URC-CM14UR-65B280C-SG
  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, Titanium, 65B280C-TI , MPN: 65B280C-TI , UPC: 810148628703 , Code: 2CM-URC-CM14UR-65B280C-TI
  • CMMG Dissent, Mk3, 6.5mm Creedmoor, 20 inch Upper Receiver, 1-8 Twist, 5/8 x 24, CMMG ZEROED Muzzle Brake, Cerakote/Hard Coat Anodized, Charcoal Green, 65B280C-CG , MPN: 65B280C-CG , UPC: 810148628666 , Code: 2CM-URC-CM14UR-65B280C-CG
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