I've read enough here and elsewhere that I think I have a handle on which primers are safe in an AR15; what about large rifle primers for similar rifles in .308, 6.5 CM etc? Obviously CCI 34 would be best, but I'm out and there are none to be had.

My specific problem presently is what to use in some .308's for a FAL, I have CCI 250's, Sellier and Bellots and recent production WLRM's that are likely candidates. Any of those I should avoid? Would prefer to use the Winchesters because I have brass already primed with them, but that is merely a timesaver.

Thanks in advance.

I run a lot of BR2's in my Creedmoor and 308:



I've never had an issue with regular ol CCI 200's either. If all you have is magnum primers, use them.

If I remember correctly, all the large rifle primers were the same thickness except of course the CCI 34’s.

Some primer stuff
https://www.sksboards.com/smf/index.php?topic=56422.0

TWR, have you ever used large rifle primers in an AR10?

Yes, mostly Fed 210M but I also loaded some Winchester. I ran the 150 grain NBT’s to 29something with Varget in my 16” Armalite way over pressure, enough to pull rims but no primer problems and no slam fires.

http://www.jamescalhoon.com/primers_and_pressure.php

Yes it was written in 1995 but says LRP’s listed are all the same cup thickness.

I put a Rise trigger in my AR-10, and had to put in a stiffer spring because of a light primer strike, I believe the ammo I tried at the time was some of my reloads, with CCI 200 LR primers.. Anyway, fast forward a few months, and I've been loading up some more ammo for it. LC cases, surplus 844 and 846 powder, a mild charge, 150 grain FMJ, and for primers I used some old Magtech LR primers I was wanting to use up. So far, the rifle has shot them with no issues.

In my case, I don't believe what I have is a primer problem, but a problem with putting in a trigger with a hammer spring that is a little on the light side. The support guy I talked to at Rise told me that I can go with an even heavier spring if needed, and I may change it again, just for peace of mind.

I'll add that if I could have found some of the CCI 34's, that's what I would have preferred to use.

Thanks friends. Sounds like I'll be fine with the Winchesters. Was a little concerned due to their new small rifle primer's poor reputation for "softness".

I have had slamfires in an AR-10 using Federal 210M's, so I avoid all Federal primers in all AR's both 10's and 15's.

I use CCI's and have never had an issue. I would be a little concerned about using any Winchester primer though. Be damn sure you (OP) check to make sure they are not part of the recall they had a couple years ago.