Primer cratering on all loads

[25WSM]

Piercing can happen when the pin is too loose. Try a cci450 primer. They are tough. Also ask Mossberg to fix it. How hard is it to make a hole and a pin have a .001 fit? I'm talking to you too Remington.

 

[Deleted member 107796]

Same here with having a Win model 70 in 7wsm that craters every primer but with no other evidence of high pressure, and never had a pierced primer, but these craters here seem lifted and quite different.
Thanks for posting this, as I just inspected my bolt and it certainly does have a chamfered pin bore. Mystery solved. Good luck with solving your issue.

 

[Westfork]

Piercing can happen when the pin is too loose. Try a cci450 primer. They are tough.

Primers in question are CCI 400, they should have the same cup as CCI 450s, shouldn't they?

Firing pin hole is not beveled, bold face is flat... I'll check the fit of the pin when I have time, it seemed OK when I had the bolt apart.

 

[Elkcrzdinmt]

I had the same cratering issue. Did a bunch of research, was going to get the firing pin bushed. When I talked to my gunsmith, he said that Remington did that on purpose. They say that they found that it creates less chance for a pierced primer on hot loads, if I remember correctly, as I went through this in 2010. My smith even made me a copy of the bulletin from Remington so that I could see it with my own eyes.

 

[willowwolfe1975]

Built a 223 Rem on new 700 action. I'm getting cratering on all loads fired, even factory. A few of my handloads even pierced primers.
I'll try to list as many things as possible to eliminate questions or things to check.
Rifle is 700 build on new action. I trued action using Manson receiver accurizing kit. Bolt face and lugs squared. Closes on GO and does not close on NOGO. Barrel is 20" Green Mountain full profile 1-8 twist.
Firing pin diameter: .075"
Firing pin hole: .078"
Firing pin protrusion: .052"
Handload is once fired Starline brass that was first fired in this rifle. I did not bump shoulder when resizing.
Overall the rifle fires great and have not seen any signs of over pressure in load workup. Other than primer cratering even on lower loads. I have also included a taget fired at 100yd while doing bullet seating testing.
I also tried swapping out the firing pin assy from another used 700 to see if possible weak firing spring spring.
Thoughts?

Hi,
I can't speak to the pierced primers, but I see a lot of other guys have already.
I have many rem 700's and of those 4 of them crater every primer despite loads or components.
I've read somewhere when I first had the issue that some 700's just do this.
Mine have never created an issue. I just use them like that.
I'd really like to know the answer to the ported primer issue though.

 

[LanceS4803]

I had the same cratering issue. Did a bunch of research, was going to get the firing pin bushed. When I talked to my gunsmith, he said that Remington did that on purpose. They say that they found that it creates less chance for a pierced primer on hot loads, if I remember correctly, as I went through this in 2010. My smith even made me a copy of the bulletin from Remington so that I could see it with my own eyes.

Interesting info.

 

[TJAY]

It is my understanding that 400 and 450 are not the same. 450's are designed for higher pressure than 400's. At least that was what I have read.

 

[25WSM]

450s will help with the piercing. As the crater developes it lets the cup get thinner as it has to stretch some to form the crater. Bushing it will stop the craters. If your loads are in book spec they will hurt nothing. If you pierce a primer back off that load. Pierced primers will etch the firing pin hole. Yes this will make bigger craters. Shep

 

[25WSM]

By the way the small firing pin will end all of this. That's why most custom actions come with the smaller pin. Even for standard and mag shells. Shep

 

[bigedp51]

All the OP has to do is look at his bolt face with a magnifying glass and if he has a beveled firing pin hole in the bolt face. If it is beveled then that is causing the problem and the only fix if he doesn't like it is to have the bolt bushed.

And the thinner primer cups are made for lower pressure cartridges like the .22 Hornet. With the AR15 it is recommended to use primers with a cup thickness of .025 to help prevent slam fires.

Primer Info & Chart + Milspec Primers for Semi-Autos & Other Primer Applications
CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
http://www.sksboards.com/smf/index.php?topic=56422.0

NOTE 1: According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably.

Below the CCI #41 primer cup is thicker on the bottom and has a shorter anvil and requires more force to set the primer off.

 

[DSheetz]

Did you fire the factory loads before the reloads ? Could you have left some resizing lube on the brass or perhaps get some gun oil in the chamber ? What is the depth to the lands after the throat ?

 

[DoubleGobble00]

I had the same cratering issue. Did a bunch of research, was going to get the firing pin bushed. When I talked to my gunsmith, he said that Remington did that on purpose. They say that they found that it creates less chance for a pierced primer on hot loads, if I remember correctly, as I went through this in 2010. My smith even made me a copy of the bulletin from Remington so that I could see it with my own eyes.

That's interesting and I first I've heard this. I only have this problem on a rem 700 action I bought in the last couple years directly from factory. It's definitely true that you should never pierce a primer with a hot load. Here are some pictures of a few hot rounds with my gun. The primer crator just grows...

 

[Naymola]

Ship your bolt to Greg Tannel at Gre'Tan Rifles and your problems will be alleviated and you'll be able to shoot any primer you want. I've got a bunch of his rifles and non of them pierce primers. https://www.gretanrifles.com/product-page/bush-firing-pin-hole-turn-pin. It is money well spent and the turn around time is excellent!

 

[Naymola]

Ooops, I just took a closer look at his website. He's talking 12-14 weeks now. He used to do it in one week. Still worth it, you won't be sorry!