i sold a friend of mine a like new Begara B14 hunter in 6.5 creed a few days ago and he's took 3 deer with it since, today he let his son use it ,sitting in a box blind and his son pulls down on a buck and "SNAP" , does not fire, shucks another round and it fires off, killing the deer. Theses were handloads that i give him to use with the rifle, he sent me a pic of the round and the primer looks like to was struck enough to set it off .. Any ideas what caused this ? The primers i used are Federal 210.