the other day a buddy of mine and i were shooting...as he made a shot he jumped and said something bit him on his right arm..well come to find out it was a primer that had been blown out of the case and landed on his arm...he was shooting a pof 308..all factory...the ammo was black hills 175 smk..factory....this happened a couple times throughout the day,,,i also shot the same ammo through my sr-25 with no problems...what could be causing this problem...a bad couple of rounds or mabe there is something wrong with the rifle?