yes it is definatley a crack, I am a hanloader but I stay within safe loads( i dont go over manual loads) i usally compare 3 or 4 diffrent books when working on loads, my hunting load is 180gr projectile on 55.5gr of imr 4350, the rifle has a few rounds thru it, around 1500 mostly 168gr bthp and 180gr psp sierra that i hunt with, but what brought it to my attention was my head bolt retaing pin broke and once i broke it down and inspected it further i found the crack in the body but none in the head or locking lugs themselves, thanks for all the help.