This CMMG bolt carrier group is built for the 6.5 Grendel and 6mm ARC, which share a common Type II bolt face. It ships fully assembled and ready to run in a matching upper.

Features:

• Complete AR-15-pattern bolt carrier group
• Chambered for 6.5 Grendel / 6mm ARC (Type II bolt face)
• 9310 steel bolt
• 8620 carrier, chrome-lined
• 4140 extractor
• Phosphate finish
• Fully assembled

This is a Type II bolt face, NOT a 5.56 BCG. Pair it only with a 6.5 Grendel or 6mm ARC barrel.