04-10-2019, 03:23 AM
Out of spec upper reciver. The 556 barreled upper and grendel mag seats fine.
Grendel upper the grendel mag is hard to seat.
You have a out of spec upper. It's dragging the bcg badly and making it somehow not fully seat and properly lock up. And your fighting the bolt lugs and barrel extention lugs too break free of each other and extract.
Pick you up a stripped upper of your choice and strip all the parts from the grendel upper and rebuild it with the new one.
Should fix the problem. Are call the place you bought it from and see if they will replace it.
Grendel upper the grendel mag is hard to seat.
You have a out of spec upper. It's dragging the bcg badly and making it somehow not fully seat and properly lock up. And your fighting the bolt lugs and barrel extention lugs too break free of each other and extract.
Pick you up a stripped upper of your choice and strip all the parts from the grendel upper and rebuild it with the new one.
Should fix the problem. Are call the place you bought it from and see if they will replace it.