Small pistol primers in AR ammo???

daves762

Private
Minuteman
May 9, 2011
0
0
47
Montana
I went into the reloading room to finish a batch of rounds for my M4.
When I reached for the box of small rifle primers it was actually a box of small pistol primers.
I cannot be sure that I accidently used the small pistol primers instead of small rifle primers, but as I re-played the day before in my head I just might have grabbed the small pistol on accident........

The load is
55fmj
LC brass
24gr H355
light crimp.


I have loaded up to 26gr of H355 in this M4 int he past so the 24 gr loads aren't too hot.

My question is........should I cautiously test them out to see if they work, or disassemble the whole batch....

ps I was tossing them onto a pile of about 1500rds so It would be hard to find all of them.......stupid I know.....

please advise.......

Dave
 
Re: Small pistol primers in AR ammo???

I would try and fish them out of the pile. Perhaps the primer color is just slightly different or has a different level of shine to it?

Since it is much higher psi than pistol, the rifle primer has thicker cup metal to handle it. So the thinner pistol primer will pierce at the firing pin impact point, and let some hot gas back to etch your boltface. A few I could live with, verses disassembling 1500 rounds, or even the top 500 in the pile, but I would make the effort to get them out.
 
Re: Small pistol primers in AR ammo???

As stated above Small Pistol Primers will pierce at rifle pressures and etch your boltface. Suggest you pull them down. I know it a bitch, but the school-of-hard-knocks is a valuable lesson.

good luck

Jerry
 
Re: Small pistol primers in AR ammo???

+ 1 jerry

safety frist. i'd pull them, i could never read pressure signs from cases fired in an AR ,everything looked the same , i use a pressuretrace II.
 
Re: Small pistol primers in AR ammo???

One problem is slam fires with pistol primers since ARs have a floating firing pin and pistol primers have a thinner cup. I never tried it, but a couple of guys tried it during the primer shortage and got slam fires fairly often.
 
Re: Small pistol primers in AR ammo???

I use both pistol and rifle in my 45 WinMag M1 Carbine conversion with no problem's.
Pull 1500 rds. down?
Why not remove the top 2 inch's of loaded ammo.set them aside and fire them next time out?
 
Re: Small pistol primers in AR ammo???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: zuke</div><div class="ubbcode-body">...Why not remove the top 2 inch's of loaded ammo.set them aside and fire them next time out? </div></div>

Etched bolt face minimum; damaged face a possibility.
 
Re: Small pistol primers in AR ammo???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">Pistol primers aren't as tall as small rifle primers.

You will likely see a lot rounds near the top of that pile which have deeply seated primers and you can likely sort them this way. </div></div>

This is not the case with small primers. They are the same size.