Some ARs advertise the barrel is high pressure tested (HPT) and magnetic particle inspected (MPI). IIRC, some advertise those same tests for the bolt...
Apparently, hot with SOF, much more thump and range than 7.62, much lighter than a .50. Why not use 300 Win Mag? That's more common in the US arsenal...
You order / pick up the rifle you wanted, inspect it thoroughly, more than most people do so the counter guy may be a little annoyed, but forget him...