The CMMG RESOLUTE Mk4 6.5 Grendel Upper Group, 16.1-Inch (CMMG part no. 64BCF88AB) is built for flat-shooting work at medium to long range. CMMG says 6.5 Grendel offers efficient ballistic performance native to many 6.5mm bullet designs, and this Mk4 upper works with any standard AR15 lower group. The 16.1-inch barrel has a 1:8 twist and a ZEROED SVB Brake threaded 5/8×24. It is finished in Armor Black Cerakote and comes with a CMMG EML15 M-LOK handguard.

Key Specifications

• The chambering is 6.5 Grendel, a cartridge known for flat-shooting medium to long range performance.
• The barrel length is 16.1 inches with a 1:8 twist and a medium taper contour.
• The barrel is 416 stainless steel with CMMG’s SBN finish.
• The muzzle device is a ZEROED SVB Brake, threaded 5/8×24.
• The upper group weighs 4.3 pounds and measures 25 inches long.

Frequently Asked Questions

What lower does it fit? CMMG says this Mk4 upper group is built on the Mk4 platform and works with any standard AR15 lower group.

What comes with the upper? CMMG says its upper groups come complete with a bolt carrier group and ZEROED accessories, including a polymer dust cover and an ambi charging handle.

Buy the CMMG RESOLUTE Mk4 6.5 Grendel Upper Group, 16.1-Inch, ZEROED SVB Brake, Armor Black

Grendel performance is only a bolt carrier group and lower away. Order the upper with our other AR-15 uppers from CMMG. Order from our Lubbock, Texas gun shop for fast, direct shipping.