CMMG Banshee Mk3 12.5-Inch Upper Group, .308 WIN Black

The CMMG Banshee Mk3 Upper Group in .308 WIN (brand part no. 38B92D0AB) proves that building an AR in a larger caliber like .308 doesn’t require sacrificing portability. This Banshee Mk3 chambering is just the thing to complete a go-anywhere .308 AR-10, built on CMMG’s Mk3 platform, which is based on the popular DPMS Gen 1 high-pattern LR308 design for broad parts compatibility. The upper group ships complete with a bolt carrier group and CMMG’s ZEROED accessories, including a .308 polymer dust cover, an AR15-pattern ambi charging handle, and a linear compensator. It runs a compact 12.5-inch, 4140CM SBN barrel with a 1:10 twist on a direct impingement operating system, a 0.750-inch non-adjustable gas block fed from the mid gas port location, a billet 7075 T6 aluminum upper receiver, and a CMMG EML11 M-LOK handguard finished in standard Cerakote. Overall upper length runs approximately 22.2 inches and it weighs about 5.1 pounds. Because this upper ships without a lower receiver, it is not itself a complete firearm; a 12.5-inch barrel is under the 16-inch federal minimum for a rifle-configured (shouldered) lower, so this upper group should only be installed on a registered short-barreled rifle, an NFA-compliant braced pistol build, or a pistol-configured lower to stay compliant.

Key Specifications

• Chambered in .308 WIN on the Mk3 platform, based on the DPMS Gen 1 high-pattern design.
• 12.5-inch barrel length with a 1:10 twist rate.
• Barrel material: 4140CM SBN, direct impingement operating system.
• Ships complete with a bolt carrier group and CMMG ZEROED accessories.
• Upper receiver: billet 7075 T6 aluminum.
• Handguard: CMMG EML11 M-LOK.
• Overall length approximately 22.2 inches, weighing about 5.1 pounds.

Frequently Asked Questions

Does this upper group include a lower receiver? No, this is an upper group only and requires a compatible AR-10/.308 lower to complete a firearm.

Is a 12.5-inch barrel legal to run on any lower? Only on a registered short-barreled rifle, an NFA-compliant braced pistol build, or a pistol-configured (non-shouldered) lower; installing it on an unregistered rifle-configured lower would create an illegal short-barreled rifle.

What receiver pattern is this upper built to? It’s built on CMMG’s Mk3 platform, based on the popular DPMS Gen 1 high-pattern LR308 design.

Buy the CMMG Banshee Mk3 12.5-Inch Upper Group

Order it from our Lubbock, Texas gun shop for fast, direct shipping to your door, and build a portable, powerful .308 AR-10.

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