Primer blowout

uncle ben

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This happened to me today. Did it on a few seperate loads. Is this caused by a bad batch of primers? Two of the loads were new, but one was a tried and true load that I haven't had any problems like this before. Any advice would be appreciated. Thanks!
 
If it's a well known load, I'm going to guess stretchy primer pockets. textbook pin cratering and gas leakage, if you're not showing extractor marks or having issues ejecting, it's probably pockets. Do you uniform? are the cases trimmed to length?

Hard to make out the head stamp on my phone but looks like federal. fc cases can vary quite a bit in life expectancy, I've had some range pick ups go 20 fl resizes and some new stuff last 5.

Might want to start your next batch of reloads with new brass :)
 
It has nothing to do with the brass, t's a known issue with Winchester primers, stop using them, or you will damage the bolt face even more.

Op never said Winchester lol. Win primers are too thin for high pressure loads for sure but neither primer is pierced. That's gas leakage.

Uncle Ben, would be helpful to know what your load specifics are?
 
Primers aren't pierced, there are pinhole failures in the corners of the cups. Not sure they are Winchester primers as they are nickle plated.
Loose primer pockets and max loads can do this though. Boltface is probably pitted now.
 
Op never said Winchester lol. Win primers are too thin for high pressure loads for sure but neither primer is pierced. That's gas leakage.

Uncle Ben, would be helpful to know what your load specifics are?

Yes it's gas leakage, but it's not leakage between the primer and the case, you can see the holes where the primers ruptured.

Loose primer pockets and max loads can do this though.

Loose primer pockets often result in gases passing between the primer and the case, they don't usually result in the primers rupturing like the ones shown.
 
Current production Winchester since 2000 is unplated. Some lots of their product have reports of blowouts.

What cartridge, what primers?

Not all small rifle primers are suitable for .223 Rem reloading, for example.
 
Current production Winchester primers purchased at Cabelas in April.

Regardless Ben, somethings wrong. Toss that batch of cases (With federal brass you're out like 6 bucks), back off a full grain and start again.



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first load was 27grains of h335 with cci small rifle primers. Projectile 40gr flat bottom nosler. Fired 12 rounds, 2 blew holes in primers. Chrono speed was 3997ft/s 3628ft/s 3465ft/s, kinda all over. Now that I know what I'm looking for, I can see cratering on other primers as well as flattening of the primers. I think this load is just too hot.

Second load was my old recipe that hadn't given me any issues in the past. Remington bench rest primers with 25 grains of h335, nosler 40gr boat tail. Fired about 75 rounds out of this batch, and two had holes in the primers. Primers not flattened, but cratered.
Gave me about 3536ft/s, 3511ft/s, 3482ft/s out of 18" barrel.

Third load was mix of cci small rifle and Remington bench rest primers. 26.5 grains of h335, nosler 35 grain spitzer. Fired 50 rounds, had 4 blowouts all on cci primers. Lighter cratering on primers. Running 3635ft/s, 3522ft/s, 3572ft/s on the chrono.

Last load was Remington bench rest primers, 22 grains with a 69grain hpbt. Shot 26 rounds, primers all show cratering. Speeds were 3016ft/s, 3057ft/s, 3055ft/s
 
It looks like those primers are showing some pretty significant cratering (as mentioned earlier) The velocity is way above the peak published velocity in the Hogdon load tables too. Will all the fired the cases still fit into a .223 shell holder? If not, they have expanded due to being way over pressure.
That's some fairly aggressive gas cutting on your bolt face. Maybe you should have it evaluated by a qualified smith.
At the very least, I would back off on the powder by at least a grain or two and see if the load works better.
I had an overpressure load this year and when you see a bunch of gas come out of the receiver, it's a real eye opener. To me it said "dude, you got lucky this once"...I don't care to try it again.
 
I sometimes get significant cratering even at starting velocities with some rifles.... I came to the conclusion that primer cratering around the pin wasnt much of an indication for me.
When the primer starts to flatten(ring all around reduced), you are near max. When it's really flat(almost no more ring), you are above max. At 27 you might be (depending on your rifle and velocity, below, at or above max). Usually comes with harder bolt lift also. Semi auto hides that.

Max velocity should be around 3700 in a 26'' barrel with around 27 according to hdy. That tells me you are over pressure.

Double check powder charge, primer seating feel and depth, bullet seating depth,

something is wrong with your rifle, or load, or both.

Try a box of factory ammunition.
If all factory ammo is fine, you have an issue with your reloads. Find it.
If factory ammo does the same, you have an issue with your rifle. Have it checked.
 
Cratering around the firing pin strike is often the result of a loose fit between the firing pin and the bolt face, rather than the result of too much pressure.
 
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