06-27-2011, 11:26 PM
Did you bed barrel extension to receiver? Barrel nut to thread tennon and gasblock to barrel?
Normally a loose barrel nut gives a somewhat triangular 'pattern' but not all of the time. Remember Grendel bbl torque is 65 ft lbs MINIMUM. If you didn't tighten, and loosen 3x the barrel nut to get over to the next gas tube try, give a shot, if you didn't premptively stretch the tennon, first two shots will do that and the barrel will be loose again. ALSO, make sure gas tube is NOT making contact with the carrier key! Utmost important. Check alignment of barrel nut and make sure it is not touchng the gas tube forcing it left to right.
Normally a loose barrel nut gives a somewhat triangular 'pattern' but not all of the time. Remember Grendel bbl torque is 65 ft lbs MINIMUM. If you didn't tighten, and loosen 3x the barrel nut to get over to the next gas tube try, give a shot, if you didn't premptively stretch the tennon, first two shots will do that and the barrel will be loose again. ALSO, make sure gas tube is NOT making contact with the carrier key! Utmost important. Check alignment of barrel nut and make sure it is not touchng the gas tube forcing it left to right.