Brownells Brownells AR-15 6.5 GRENDEL BOLT NITRIDE MP 2857 Brownells AR-15 6.5 GRENDEL BOLT NITRIDE MP 2857 The Brownells M16 6.5 Grendel Complete 9310 Bolt Assembly is built to withstand heavy-duty use in both semi-auto AR-15s and full-auto M16 rifles and... MSRP: Was: Now: $60.00 Out of stock