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View Full Version : Primers popping out!!


myshoulderissore
May 20, 2012, 12:21 AM
Good evening all! Just got back from shooting my 7mm Rem Mag, ran out of my favorite load and it's no longer being produced, so I went with Hornady Superformance 139gr GMX. Well, I shot 12 rounds, and 3 of them lost their primers as they ejected, a few more have powder burns around the primer, and they broke my ejector... See pics for more details.

What is going on here? I did some work on my rifle over the last few days, but it was bedding it, so I assume it's not me, is the ammo faulty or too hot? Should I contact Hornady and see what they say?

http://photobucket.com/wtfrounds 2 more pics here

http://i195.photobucket.com/albums/z16/mattacorn/Hornady%20Superformance%207mm%20Rem%20Mag/WTFroundsclose.jpg

DnPRK
May 20, 2012, 12:23 AM
That ammo is over pressure in your rifle. I wouldn't use that ammo any more or it will etch your bolt face.

ruger357w
May 20, 2012, 06:05 AM
yup. I would say over pressure

TheNatureBoy
May 20, 2012, 06:07 AM
I agree.

was123
May 20, 2012, 07:02 AM
Definately over pressure in your rifle. Stop shooting those immediately. I have a 7mm-08 that has heavy bolt lift when using the Hornady Superformance ammo.

wingman
May 20, 2012, 07:10 AM
I would contact Hornady send picture or a case, sure is sign of over pressure.

kraigwy
May 20, 2012, 07:11 AM
I'm gonna go the other way.

If it was high pressure, the rear of the cases would have shown more pressure signs, you would notice it by the lettering on the rear of the case.

Too low of pressures would also cause the primers to come out, plus the smoking you have.

To see what I mean, load some pistol cases with just primers, no powder, no bullets. You'll see the primes will back out.

High pressure would cause the lettering to be smashed out of shape. Also the remaining primers don't look flattened out like what happens with high pressure.

This is just something to look at going only by your pictures.

Jimro
May 20, 2012, 07:56 AM
I agree with Kraigwy, if this were a high pressure situation I would expect to see some glaring bolt wipe on the case head. It could be there and just not photographed well.

I'd call Hornady with the LOT Number and send them the pics. Because either low or high pressure is a bad thing for safety.

Jimro

dahermit
May 20, 2012, 07:57 AM
Whether it is high or low pressure, it is like the guy who is hitting himself in the head with a hammer because it feels so darn good when he stops. Those rounds are not conventional ammunition. Buy some normal rounds and see what happens with them.

mehavey
May 20, 2012, 08:02 AM
...3 of them lost their primers as they ejected, a few more have powder burns around the primer, and they broke my ejector...
This is not a low pressure problem, even if we don't see the usual ejector burnish/imprint marks. You also don't break/ruin ejectors w/ low pressure.

I suspect defective primer pockets and/or primers.
Get thee to Hornady ASAP with the pics and all other technical info you have.




ps: Measure the fired case length against that of the unfired case. See how much stretch you have

bigalshootmupper
May 20, 2012, 09:19 AM
Looking at just the symptoms of a problem makes it really hard to find the cause. To me, it looks like the cases are too short or sized incorrectly. I doubt your chamber got longer. I'd measure the case lengths and post back. Someone can tell you if they are too short, but that is only one measurement of many that can be done without special tools. I'd contact Hornady and see what they say. If they say no problems, then I'd highly recommend taking the gun to a good gunsmith and have him measure the chamber.

bigalshootmupper
May 20, 2012, 09:24 AM
I forgot to add, if you have some unfired rounds left, chamber them with 4 or 5 layers of paper in between bolt face and round. It shouldn't close or the bolt should be really hard to close. (don't force it closed or it might be really hard to open the bolt). It should allow only about 2 pieces of paper.

splatman
May 20, 2012, 09:35 AM
If there was excessive recoil when shooting these rounds then YES absolutely
those rounds were too hot. It looks to me like there is some cratering of the
primer as well. Another reason to consider reloading your own ammo. Don't shoot anymore of this stuff.

5RWill
May 20, 2012, 09:59 AM
Superformance is known to be a hot load that is over pressured. Though as kraig and Jim said you would expect to see some wear on the rim of the case. Regardless i would switch ammo or get into reloading.

Bottom line hornady's superformance has had QC issues for quite some time now.

mrawesome22
May 20, 2012, 05:15 PM
Was it hard to lift the bolt?

Sent from MIUI using Tapatalk 2.

hooligan1
May 20, 2012, 05:54 PM
Those look like your rifle might have a "headspace" problem. If it's soly an ammo problem, Hornady cs is great to work with, I hope you find the problem and get it solved.

myshoulderissore
May 20, 2012, 11:40 PM
I sent the pictures to Hornady, we'll see what they say... The bolt was tough to lift on a couple rounds, I kept shooting due to stupid curiosity. I eyeballed the fired brass next to previously fired brass and unfired ammo from the same box, no micrometer available, but it doesn't look any longer or otherwise abnormal. I have shot many rounds of various types through the rifle without problems, I don't think anything could have changed as far as the rifle internals go. I'll post updates once I know more.

rezmedic54
May 20, 2012, 11:48 PM
I had the same thing happen with some Privi 308 ammo. Turns out just bad brass primer pocket where just a tad to large and after I shot them they over stretched and primers fell out. I bet you can push primers bad in with your finger without much trouble. Was glad to find out it was bad brass as I was going nuts trying to figure out what was up with my rifle. I got a couple of boxes of brass out the deal probably get the same deal from Hornady.

warbirdlover
May 21, 2012, 01:05 AM
I don't see flattened primers in the pix. They still have the corner radius. I think the primer pockets were just too big.

Geezerbiker
May 21, 2012, 06:36 AM
A friend of mine had that happen with his .270 with super-performance rounds. He only fired 5 out of the box and sent the rest back to Hornady. They told him there wasn't anything wrong with the ammo and sent him a full box.

I wouldn't shoot Hornady super-performance rounds in any rifle I have. It's not worth the risk...

Tony

geetarman
May 21, 2012, 06:51 AM
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

madcratebuilder
May 21, 2012, 07:48 AM
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 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.

Bart B.
May 21, 2012, 08:40 AM
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.

farmerboy
May 21, 2012, 10:01 PM
Warbird answered your question for you. And Kraig and Jim were on the right track. No, it wasn't over pressure in this case.

Deja vu
May 21, 2012, 10:12 PM
I have never seen that before. I have shot a few stupidly hot loads and that has never happened.

farmerboy
May 21, 2012, 10:16 PM
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.

lefteye
May 21, 2012, 10:24 PM
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.

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.)

Hook686
May 22, 2012, 01:36 AM
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.

myshoulderissore
May 30, 2012, 09:13 PM
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.

iamdb
May 30, 2012, 09:30 PM
It looks like a headspace problem. I would get a no-go gauge and verify.