Primers popping out!!

I have the same issue with some Hornady Match brass in 22-250.

I am running handloads that are NOWHERE close to max pressure.

I thought at first it was overpressure, but now I am convinced it is a slightly oversize primer pocket and borderline undersize primers.

I can use the same load with Remington primers and get no backout. When I use Winchester, I get the backout.

I have not had any primers fall out but they are probably .005/.007 in. above flush with the head of the case.

All my brass was brand new and all was sized and trimmed to minimum OAL before I started.

Geetarman:D
 
warbirdlover said:
I don't see flattened primers in the pix. They still have the corner radius. I think the primer pockets were just too big.
Click to expand...

I agree, no sign of over pressure on the primers. Large primer pockets would be the first thing I looked at. Head space second.

Over the years I have had certain lot numbers of cases with tight pockets and loose pockets, it does happen.
 
I doubt it's an extreme low pressure situation. I've fired several primed cases testing firing pin striking force in both pistol and rifle cases, none of them backed out of the cases. There's not enough pressure built up to overcome the force of the firing pins holding the primers in the case.

Having shot loads about 15% below max that resulted in the primer backing out several thousandths, their primers were pushed out of the case several thousandths. But they didn't fall out of the case. Fired case headspace was shorter by about the same amount; evidence that the firing pin drove the case hard enough against the chamber shoulder to set it back. Peak pressure wasn't enough to push the case head back against the bolt face and reseat the primer flush with the case head.

It's probably bad ammo, as others have suggested.
 
Warbird answered your question for you. And Kraig and Jim were on the right track. No, it wasn't over pressure in this case.
 
Either enlarged primer pockets or small primers. Get yourself another box of em from a different store so you know you won't get some possibly out of same lot and they'll shoot fine. But I'd still contact Hornady, they should send you a free box or reimburse or something.
 
Quote:
Originally Posted by warbirdlover
I don't see flattened primers in the pix. They still have the corner radius. I think the primer pockets were just too big.

I agree, no sign of excess pressure on the primers. Large primer pockets would be the first thing I looked at. Head space second.

Over the years I have had cases with tight pockets and loose pockets, it does happen.
Click to expand...

I AGREE. Enough excessive pressure will flatten primers so there is little or no radius. Primer pockets too deep or too large in diameter, though uncommon, have been around for many years (nearly cost me a nice mule deer many years ago.)
 
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Let's see ... you noticed the problem with the first primer ejection but continued to shoot. hmmmm I'm not sure Hornady is the problem here.
 
Hornady contacted me today, said that the remaining ammo tested normal, 3200fps and 62k psi. I looked up the 7mm, though, and it is spec'd to 61k, not 62k. Don't get me wrong, if Hornady says it is so, I believe it. Just a curiosity question.

Anyways, they are sending a couple boxes of Custom 154gr SST ammo, recommended I not use Superformance in my rifle. Good folks, fast, nice, and generous.
 
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