CMMG BANSHEE MK4 UPPER GROUP 300BLK 8 BLK

The CMMG BANSHEE MK4 Upper Group converts an AR-15 platform to .300 BLK with an 8 barrel and ships with a ZEROED bolt carrier group and accessory set. It pairs a compact barrel profile and an M-LOK handguard for tight handling and accessory compatibility. This upper supports both subsonic/suppressed and supersonic loadings, providing flexibility across use-cases.

Typical applications include suppressed shooting and short-barrel rifle (SBR) builds, and it can also serve for close-quarters training or limited mid-range shooting with appropriate ammunition. The group is finished in Cerakote and uses standard AR-15 interfaces for installation.

Product Specifications

• The platform is Mk4.
• The caliber is .300 BLK.
• The operating system is Direct Impingement.
• The barrel length is 8.
• The barrel twist is 1:7.
• The barrel material is 4140CM SBN.
• The barrel contour is MT.
• The muzzle device is a CMMG ZEROED Linear Compensator.
• The muzzle thread is 5/8 x 24.
• The gas port location is Pistol.
• The gas block is 0.750 Non-Adjustable.
• The upper receiver material is Billet 6061 T6 Aluminum.
• The hand guard is a CMMG EML7 M-LOK.
• The finish is Cerakote Standard.
• The weight is 3.0 lbs.
• The UPC is 810097502567.

This upper group is built for compactness and compatibility: the short barrel, M-LOK hand guard, and ZEROED accessory package let you tailor the build to suppressed operation or a compact rifle platform. It provides the core components needed to convert or complete an AR-15 style upper while maintaining standard mounting interfaces.