Is the firing pin mark on the primer from being struck by the firing pin, or was it formed when pressure forced the primer against the firing pin hole in the boltface?
Looks like a high primer to me.
the "firing pin mark" is it indented or protruding?
There is so much damage to the case, it’s hard to say.... all the primers were set to depth, but some were not “super-tight” when I put them in with a hand priming tool.
Any soldiers in the group been sent out to practice with reloaded ammo?
I've looked at that pic a few times, the primer looks slightly raised, I doubt the firing pin came in contact with the primer. Also since the firing pin isn't broken I don't see how it could strike the Primer in the first place. Just how "loose" were the Primers, and how long have you been reloading? I ask because I recently had about 7 Winchester Primers that left me wondering how in the hell I had loose pockets after two firings. I marked the brass and used a few CCI 200's I had left over, nothing wrong with the pockets. I'm assuming you've inspected the Bolt, and found nothing unusual, no damage/bits missing from the Bolt and the Barrel Extension. If so high Primer, or some debris, the Primer is easy, just get into the habit of running your finger over the base of the case each case you prime (and why I'm not too keen on the idea of Priming on a Progressive Press).
Regarding the sloppy Primers, has anyone else noticed any sizing weirdness with Winchester LR Primers lately? I just put it in the Priming tool again and gave it an extra squeeze, marked the case, and set aside the 7 to use for warm up shots, it's easier to keep track of a possible bad case that way. There was definitely something wacky with those 7 Primers.
You can't really have a "Slam Fire" with this style of Bolt Carrier and Bolt like an M-14 if I'm not mistaken. I've induced a Slam Fire once with my M-305, last time I tried single loading one.
I’ve been reloading for over 10 years, and about 4-5yrs for an AR10. Never had this issue.... the primer is sticking out a bit in the picture, but that is due to the slam fire/OOB detonation. It was not like that when it went in the mag. After this close call, I’ve been doing a bunch of reading, and it is very possible to have a slam fire with soft primers in any AR. Google “Sierra Bullets reloading for AR’s) and they go to in detail the differences. Has been an eye opener.
Now I'm even more convinced that it wasn't a Slam Fire, you fed it from a Mag, that reduces the potential dramatically. As for Sierra's warning re. AR 10/15 Slam Fires, can you provide a link? My Manual refers quite clearly to Service Rifles, in the Gas Gun section of my manual, not AR's in particular, pull your BCG and move the bolt back and forth while pushing on the firing pin, it can't protrude until the round is pretty much fully chambered, and the locking lugs should already be partially engaging the barrel extension.
I'm not saying it can't be a Slam Fire, but unless I'm misunderstanding how the BCG functions, I can't see how it is.




























