Primers Ejecting?

dfritter1 said:
I would run it through a press to see what a case comes out at after re-sizing, but I haven't assembled my press yet (bought it at the Wholesale grand opening in Langley) as I don't have room on my workbench for it until I finish rebuilding my truck's motor. I've only got one buddy that shoots, and he doesn't have a press either, so I guess I'll just have to wait. In the meantime, I figure a set of headspace gauges is probably a worthwhile investment, as I will eventually be buying a Shilen barrel for this rifle anyway.
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A case will ALWAYS be over-length after its first resizing (in my experience). That measurement will tell you, basically, nothing.

Measure your cases now. No resizing, no cleaning, just put 'em in some calipers tip-to-tail. Make a table of the length of the "spit out" cases and compare them to the "retained" cases. Perhaps we'll see a trend in terms of OAL?

Also, perhaps most importantly, make a case OAL measurement of all of the UNFIRED rounds you have from that lot. Measure from base to the mouth of the case - not the bullet, just to the neck. See if there is some inconsistency there - and, MOST importantly, whether the case OAL is within SAAMI specs.

.300 WM should spec out at 2.620" base to mouth, IIRC.

If, say, you see unfired cases measuring 2.625"... well, that's a problem - especially if the chamber is tight or dirty.

-M
 
Oh, and if you're feeling adventurous, rub a light coating of gun oil into your chamber, plug it just forward of the "leade" (throat) with some cotton, and make a molten sulphur cast of the chamber. Measure that and you'll see if you have a proper SAAMI-cut chamber, a match chamber, a damaged chamber, etc.

-M
 
Doc M said:
Oh, and if you're feeling adventurous, rub a light coating of gun oil into your chamber, plug it just forward of the "leade" (throat) with some cotton, and make a molten sulphur cast of the chamber. Measure that and you'll see if you have a proper SAAMI-cut chamber, a match chamber, a damaged chamber, etc.

-M
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Why not just measure one of the fired cases?
 
H4831 said:
Why not just measure one of the fired cases?
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That's what I do on mine, yes.

Because he seems to be having inconsistent case dimensions - even in the shoulder - I thought a sulphur cast would square it away once and for all.

You're right though, a well-formed case basically becomes a chamber 'casting.' Perhaps a chamber 'swaging'? :)

-M
 
Doc M said:
A case will ALWAYS be over-length after its first resizing (in my experience). That measurement will tell you, basically, nothing.

Measure your cases now. No resizing, no cleaning, just put 'em in some calipers tip-to-tail. Make a table of the length of the "spit out" cases and compare them to the "retained" cases. Perhaps we'll see a trend in terms of OAL?

Also, perhaps most importantly, make a case OAL measurement of all of the UNFIRED rounds you have from that lot. Measure from base to the mouth of the case - not the bullet, just to the neck. See if there is some inconsistency there - and, MOST importantly, whether the case OAL is within SAAMI specs.

.300 WM should spec out at 2.620" base to mouth, IIRC.

If, say, you see unfired cases measuring 2.625"... well, that's a problem - especially if the chamber is tight or dirty.

-M
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This is what I was suggesting that you do in my first post. You have experienced an inconsistent problem with the expanded primer pockets, so measuring the length ONE unfired case tells you exactly nothing.
Also, the picture comparing two fired cases shows drastically different case neck lengths. Are you certain you didn't have the captions mixed up? it seems to me that the one on the right with the very sharply defined shoulder and extra long neck would be the one that developed higher pressure to spit out the primer, not the one on the left with the short neck and lots of radius left on the shoulder. Just a thought...
 
toomanygunsI have seen factory ammo that blew out the primers before.
When Remington first came out with there RUM some of the first batches of ammo were too hot.
 
You seem to have multiple problems and no obvious solutions. Judging by the
way each cartridge face is marked, whether it dropped the primer or not, my
guess would be (and it's just a guess on my part) is there is oil, or some other
lubricant, on the chamber walls, or the dimensions of the chamber are not
what they should be. I would measure the diameter of the spent cartridges as
compared to the unspent cartridges and I would make sure the chamber is free of
any oil or grease etc. How all the above would lead to the primers falling free
is beyond me. Maybe you just got some bad ammo, but I have my doubts
about that. Good Luck.
 
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The case head is solid brass. It has been extruded into the ejector hole on the bolt face. This requires pressure north of 70,000 psi. This is serious stuff.

It is either bad ammo or a chamber problem. Trying a box of Remington or Federal for comparison would be a good start. If it was me pulling the trigger, I would shoot it from the hip to keep my face away from the action. If other ammo has no problems, i would send Winchester ammo back, with an email heads up with pictures, so they can react quickly, if needed.

If it is an ammo problem, it could be wrong powder, contaminated powder or wrong bullet. I have seen them all.

If other ammo has problems, it is the chamber.

Have you measured the length of the barrel? If it is short, the barrel may have been set back and re-chambered with a tight neck or otherwise non-standard chamber.

A worn reamer will give a tighter neck. But not that tight....
 
Well, after running a set of GO/NO GO headspace gauges through the rifle and casting the chamber, I couldn't find anything amiss.

So I went out and shot it. And it exploded.







I kid, I kid. Actually, nothing went wrong at all. I fired the other box of 20 rounds through it and checked each round upon ejecting; no primers loose or missing, no ejector stamping, no misshapen shoulders. Each one came out uniform and intact. Once I'd gained a little confidence, I popped in one of the two remaining rounds from the old box I'd been using when the primers were ejecting. Again, I pulled the bolt back and watched a perfectly formed case, primer intact, pop out of the chamber. Threw in the last remaining round from the old box, pulled the trigger, and was again rewarded with another casing ready for the reloading bench.

So, I've chalked the problem up to the effects of water on the brass. I shot these last 22 rounds on a hot, dry day with nary a drop of water to be found, and everything functioned perfectly. It makes sense to me that water, turning to steam, would artificially increase the chamber pressure outside the casing, preventing it from expanding to fill the chamber, hereby popping out the primers and preventing the case from fire forming properly.

In any case, I'm glad I took the steps I did, and I'm even more glad that I don't have to rush out and buy that new barrel just yet! Thanks for your help guys!
 
It happened four times over 18 rounds of factory Winchester Super X
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No offence drifter but I 'll say this for the next newbs benifit: continuing to feed and fire rounds that are not behaving as they should is just plain stupid. The trigger is not an anaylitical tool. If you don't know what is happening STOP. What did you hope to accomplish by continuing?


I know it is awfully hard to hurt yourself with a rifle but pay heed to what Ganderite points out:

It has been extruded into the ejector hole on the bolt face. This requires pressure north of 70,000 psi. This is serious stuff.
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To make you feel better about once every 6 months someone posts a similar "I had no clue and kept shooting" thread.
 
Well, I yelled stoppage at the top of my lungs, saw the bolt was fully to the rear, so I reloaded and popped off another round as quickly as I could!

Actually, truth be told, I had heard stories of primers coming out in the wet so I didn't give it that much thought while I was out there, but didn't notice the ejector stamping. It was really raining... think of inspecting brass while in the shower.

Who here diligently inspects their case heads after each round, out of curiosity? Last I checked you don't exactly want to pull out of your shooting position to look for/pick up/check out your brass in the middle of a group... but that's just been my experience.
 
That's one finicky rifle if shooting in the rain caused that! I was wondering that being a savage if maybe someone monkeyed around with the barrel and barrel nut for some reason; thus changing the headspace.
 
Checking the brass while shooting this weekend drove me nuts, actually. I finally got a left-handed rifle and I had to put the damn thing down between every shot!

Curse you wrong-handedness! ARGH!
 
Who here diligently inspects their case heads after each round, out of curiosity? Last I checked you don't exactly want to pull out of your shooting position to look for/pick up/check out your brass in the middle of a group... but that's just been my experience.
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I do until I am 100% certain of the batch.
So your group was just so tight with those rounds and your spotter was so excited that you figured you were on the verge of a new CGN record, I understand LOL. You said you noticied the primer rattling around in the action and then still did'nt inspect your brass in addition to continuing to fire. I got no problem with folks making thier own judgement calls about thier saftey I just wanted to point out that there is risk involved in replicating your actions.
What really boggles me is how you could still see the target through the rain that kept you from seeing a case head at arms length.
 
Alright, I'm convinced. I will now check my case heads, bolt face, headspace, and bore diligently after each shot. Especially after factory ammo!
 
well I was hoping to chime in before the conclusion because I myself have seen my shoulders round off, and ejector extrusion from chambering wet shells in my .300 savage. I never had a primer fall out, I wasnt shooting anything too hot that day either. Watch what happens when you full length resize with too much lube, you'll get the same rounded corners and even dimples between neck and shoulder.
 
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