CMMG Mk4 6mm ARC Resolute Upper Group Receiver

Chambered in 6mm ARC, this RESOLUTE Upper Group is designed to pair with any standard AR15 pattern lower group. Harness the capability of 6mm in this uniquely designed RESOLUTE 16.1 upper. Specifications for CMMG Mk4 6mm ARC Resolute Upper Group Receiver: Manufacturer: CMMG Cartridge: 6mm ARC Overall Length: 16.5 in Barrel Profile: Medium Tapered Gas System Length: Pistol Length Barrel Twist Rate: 1-7.5 Threads per Inch: 5/8×24 Muzzle Device: CMMG Zeroed Muzzle Brake Fabric/Material: 7075 T6 Aluminum Gas Block Journal Size-Diameter: .750 in Gun Rail: M-LOK Gun Type: Rifle Gun Make: CMMG Gun Model: CMMG Mk4 Weight: 3.9 lb Magazine Included: No Mount Type: M-LOK Package Contents: CMMG Mk4 6mm ARC Resolute Upper Group Receiver