02-09-2012, 12:20 AM
cjgemm Wrote:Would there be any benifit from setiing up a barrel with an ARP "super bolt" instead of a Grendel bolt.
It depends on if the extra mass can make up for the sulfur content in the 9130. Armalite experienced this problem when the sulfur in their barrel liners produced weak veins upon being heated and subjected to pressure during the initial trials of the AR10, and barrels burst.
I would want a Superbolt made from the Milspec steel for an M4 bolt, since I know of some 9130 bolts that have broken. They broke because of an upper that had an extension with a face that wasn't true, and was torquing the lugs unevenly. I've read from others claiming to be metallurgists that Carpenter 158 is the steel used in military contract bolts, heat-treated to a certain standard, but that Carpenter 158 is difficult to obtain in small volumes. I don't know because I'm not a metallurgist, or small shop who orders steel stock.