CMMG BANSHEE MK4 Upper | 5.56×45 | 12.5

The CMMG BANSHEE MK4 upper group is a compact AR-platform upper designed to pair with Mk4 or standard AR-15 lowers to create a compact AR pistol or short-barreled rifle (SBR). It ships complete with a bolt carrier group and ZEROED accessories, and is finished in CMMG’s standard Cerakote. The design emphasizes compact handling and compatibility with common AR-15 lower assemblies.

Typical applications include short-range target work at the range and use in compact carbine or pistol configurations where maneuverability and carbine-like ballistics are desired.

Product Specifications

• The platform is Mk4.
• The caliber is listed as 5.56mm (5.56x45mm).
• The operating system is Direct Impingement.
• The barrel length is 12.5.
• The barrel twist rate is 1:7.
• The barrel material is specified as 4140CM SBN.
• The muzzle device is the CMMG ZEROED Linear Compensator.
• The muzzle thread is 1/2 x 28.
• The gas port location is Carbine.
• The gas block is 0.750 Non-Adjustable.
• The upper receiver material is Billet 6061 T6 Aluminum.
• The hand guard is the CMMG EML11 M-LOK.
• The finish is listed as Cerakote Standard.
• The charging handle is the CMMG ZEROED Ambi.
• The UPC is 810097503960.

This upper group is a concise, purpose-built component for builders who need a compact AR upper that comes ready with a BCG and ZEROED accessories. Its configuration suits compact range setups and short-barreled configurations where reliable, familiar AR ergonomics are required.