Never seen a primer do this before.....

[MASH]

I was shooting some some loads today to try my new Lapua brass and I had two primers come out of the rifle looking like this. A guy at the range tried to tell me I had really old primers, like over twenty years old. They are Federal Small Rifle GMM, I have had them less then a year. Has any one seen this before and know what causes this? I have been shooting most of my life and reloading for a large part of it, I have never seen this before. The primer pockets where very tight when loading them, not sure if that's a factor.

 

[Korhil78]

What rifle is it? And are those the higher charged loads that got pierced?

I had this problem with my Bergara ridge and I had to send it off to Gre-Tan rifles to have the firing pin and spring changed out and bushed. Yours may not need that but we need more information to formulate an idea of what is going on.

 

[LazzInc]

I could be wrong, but looks like perforated primers to me, and I have only ever had that happen when the loads are too hot ,,,,

 

[Ross1147]

I had this happen when fire forming some 6 Dasher from 6 BR. I went down a grain in powder and changed primers from Remington 6.5s to CCI 450s. Never had it happen again.
The 4 or 5 times it happened did cause damage to the firing pin so make sure you check it.

 

[MASH]

What rifle is it? And are those the higher charged loads that got pierced?

I had this problem with my Bergara ridge and I had to send it off to Gre-Tan rifles to have the firing pin and spring changed out and bushed. Yours may not need that but we need more information to formulate an idea of what is going on.

Rifle is a Ruger American Predator, load is 40.5 / H4350 and the second row was 41.0 / H4350. Berger 140 VLD, New Lapua brass first firing.

 

[Korhil78]

Well, all of your primer hits from the firing pin are extremely deep. You will either have to load some lighter charges and see if it still does it or call Gre-Tan rifles and see what he thinks or any other competent gunsmith. If you keep allowing that to happen, the pressure from the blow back could damage your rifle.

 

[MASH]

I could be wrong, but looks like perforated primers to me, and I have only ever had that happen when the loads are too hot ,,,,

I would tend to agree but there are no other signs of over pressure, no sticky bolt, ejector marks, etc. I know different brass makes a difference buy I normal run 41.0grn / H4350 in my Hornady brass with no issues. But it's different.

 

[MASH]

Well, all of your primer hits from the firing pin are extremely deep. You will either have to load some lighter charges and see if it still does it or call Gre-Tan rifles and see what he thinks or any other competent gunsmith. If you keep allowing that to happen, the pressure from the blow back could damage your rifle.

I'll try some lighter charges and see what happens. Maybe change primers as well, but one change at a time.

 

[Korhil78]

The shell on the left is what mine used to look like before I got it fixed and it would pierce random primers. The one on the right is after I got it fixed. Noticeable difference.

 

[MASH]

Thank you for the input, I will check into that as well as changing up the load.

 

[Korhil78]

It's about $150 fix just so you know. Don't know if you want to put that much into your rifle when you can just go back to hornady brass and be fine.

 

[Barrelnut]

Try CCI small rifle primers. The cups are not only a little thicker, They are also harder.
This kinda a know issue with some rifles made for a cartridge with lartge rifle primers and then moving to small like Lapua brass.

 

[codyadams]

I have seen it several times. Either too high/nearing max pressure, or too heavy or a firing pin spring, or more likely, a combination of those. The times I have seen it were in a few 98 mausers. You likely have too heavy of a firing pin spring for use with small rifle primers, you most likely would be able to make it work with a lighter spring. However, the proper way is as stated, a lighter spring, smaller firing pin, and having the firing pin hole bushed. Bushing the firing pin will also fix any issues with premature primer cratering appearing. If cratering shows up after being properly bushed, your at or near the max for your components.

If you don't want to pay to have it worked on, do what barrelnut stated, try cci primers. Especially the magnum primers, I have noticed they don't crater as much if you have a sloppy firing pin hole.

 

[MagnumManiac]

Pierced primers are often called 'blanked, the reason is due to the appearance that a punch was used.
Yours appear to be caused by a deep firing pin strike. I would uncock the bolt and measure the firing pin protrusion.
If it is between .055"-.065", then it is in spec, if more, it needs reducing.
The other cause is from a too loose fit of the firing pin in it's hole in the bolt, bushing is the only fix.

Cheers.