11-10-2013, 04:13 PM
I guess you need to know if the chamber was bored to Type I or Type II Bolt. The Head-space is the only difference and a 7.62x39 will not work in a Grendel (new) chamber. I think a while back there were different measurements and all kinds of things during the development. Not sure when your barrel was made or the chamber. So a go-nogo gauge might be a good thing to check with. $30 in stock at Brownells.
http://www.brownells.com/gunsmith-tools-...%20Grendel
http://www.brownells.com/gunsmith-tools-...%20Grendel
