Originally Posted By: HidalgoCCI Bench Rest primers have done the job for us over many 1000s of rounds, both large & small sizes (BR2,BR4).
Although I'm certain there have been some slam fires in AR style rifles, I have yet to actually hear someone say "Yes, I had a slam fire". All I hear are heresay or rumors.
But I suppose it is better to be safe than sorry anytime we are loading or shooting our firearms.
I've actually witnessed 2, one was during the Predator Masters LBL hunt about 06'. Three of us was hunting together and the PM member was using Remington 6 1/2 primers in his AR. He chambered a round at our second stand that morning and it went off. My buddy and me was right beside him looking at him when he let the charging handle go, he definitely didn't pull the trigger either.
The other was at a clearing barrel in Afghanistan on an issued M4 and issued ammo that I'm 99% sure was due to sand/grit between the bolt face/round from a weapon that was to oily for desert operations and using the same round over and over that had been repeatedly chambered. Our SOP was for an NCO to stand beside every leaving/returning soldier of your element and witness proper clearing and loading in a clearing barrel to ensure safety and the safety was definitely on nor did the soldier pull the trigger.
Another thing that can cause an issue is primers that aren't seated properly i.e. deep enough.
Both of these first hand ADs is enough to solidify to me the importance of chambering a round in a safe direction.