7x57 Mauser

[stangfish]

You are probably over sizing your brass. If you have not torched your bolt face you are lucky.

 

[Waynzee]

So, I took my dies up to the gunsmith and had him set them up, apparently I had them adjusted wrong. They are RCBS dies, after adjusting the dies we loaded 3 rounds and tried it, the primers still moved out but not near as much as before. We also shot some Remington 140 gr. factory ammo and had the same result. So, if this rifle wasn't my Dad's and I didn't see deer and bear piled up over the years I'd stop fixing it now. But I'm going to have the barrel removed and the action checked and if possible I'll be hunting with it next year.
Thanks for all the insight and information.

 

[waltercrouse]

Checked the cases they are all good and the primer pockets are tight. Using CCI BR 2 primers. No, I don't think it's the cases because I fired some of the same rounds in a friends Ruger model 77- 7x57 and had no problem with the cases or primers.

I think you have oversize primer pockets. CCI primers are tightest primers I found, they make the primer with a thicker primer case. In fact I take CCI primers in cases that are lose in the primer pocket when I am using Winchester primers.