Cratering primer !

Kamikaze11

Kamikaze11

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Sorry for my bad english it my second language !

I was at the range today with my rem 700 , 308 1-12

Im reloading mix brass , with h4598 ,cci large riffle primer and hornady sst 165gn

The lee manual start a 41 grain t0 43 max with a oal of 2.750

I trim my brass to 2.008 ,
I made 5 round of each
40 ,41,42,43gn oal 2.800

At 40 i dont see any pressure sign
But between 41-43 i see some primer crater ,
Sign of over pressure ?

I read somewhere the new model rem 700 , the firing pin hole is tapper and is kinda normal to see some crater ! Any advice ?
 
My Remington 700 30-06 has a bevelled firing pin hole like pictured below, and like so many other Remington 700 bolts, and this lets the primer flow into the bolt face.

Check your bolt face with a magnifying glass and see if you have a bevelled firing pin hole. If you do then over pressure is "NOT" causing the cratered primers.

I contacted Remington about repairing the bolt face and their reply was this is normal and will not cause any problems.

DSCN0407.jpg


If you want you can have the bolt face bushed like below to solve to issue. Its been eight years since I bought the Remington 700 and I just live with the cratering and none of the primers have failed or ruptured.

DSCF4863-1.jpg
 
ton anglais est pas si pire!! ahahhaah

I was to talk about the bolt face too.. if it's the only "sing" taht you have , dont worry about it...
As bigedp51 said, look at it and you'll know why ;)
 
Cratering means nothing. If the primer flattens right out, then I would be a bit concerned. If the primer edge is still rounded, you are good to go.

A stiff bolt lift or an ejector mark on the case head means you are in proof load range and need to back off a full grain.
 
Lots of high energy loads will give cratering. Pretty common in .38 super loads, and lots of shooters use rifle primers which have somewhat thicker metal on the cup.

You can try a few different brands of primer, and see if it gets better or maybe worse. One of the other tricks for the pistol shooters was to use a firing pin with a diameter close to the firing pin hole in the slide; although this was to reduce the amount of primer material flowing into the tiny gap between pin and breech face hole, and didn’t really address the original issue.

As long as the primer is not leaking gasses back onto the bolt face it isn’t really a problem. I am curious how long your brass lasts?
 
Last edited:
Tokay444 said:
My Bergara B-14 HMR would crater everything, including factory ammo.
Click to expand...

I assume you have an older B14. Early models had too big of a firing pin hole in the bolt. They actually updated the bolt mainly because people were cratering SP Lapua brass in 6.5CM.

My Bergara 6.5 BMP will crater primers when I use Alpha brass. But I have a newer HMR in 308. If I use my 308 updated bolt in my 6.5 it fixes the issue. Luckily the headspace of both bolts is within .001"
 
Longboat said:
I assume you have an older B14. Early models had too big of a firing pin hole in the bolt. They actually updated the bolt mainly because people were cratering SP Lapua brass in 6.5CM.

My Bergara 6.5 BMP will crater primers when I use Alpha brass. But I have a newer HMR in 308. If I use my 308 updated bolt in my 6.5 it fixes the issue. Luckily the headspace of both bolts is within .001"
Click to expand...

I do have a pretty early model. My cast shroud never broke, but O'Dell hooked me up with a billet one regardless. The cratering doesn't bother me much.
 
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