Thread: Fixing Belted Magnum Bulge - DIY Method

Is that bulge not impending case-head separation?

Originally Posted by StrikerNZ

Is that bulge not impending case-head separation?

No but if you size with the die down hard on the shell holder trying to remove the bulge that can be a cause of head sep. The bulge needs to be removed as a separate step to prevent setting the shoulder back. The belt serves no useful purpose in many belted cases.

Originally Posted by grandpamac

No but if you size with the die down hard on the shell holder trying to remove the bulge that can be a cause of head sep. The bulge needs to be removed as a separate step to prevent setting the shoulder back. The belt serves no useful purpose in many belted cases.

Yep, originally I think it was there to set the headspacing on the old straight walled big bore cartridges. Nowadays on bottleneck cases it's a hangover that creates more problems than benefits, as most still set the cases up to headspace off the shoulder. I never thought about setting up the ER collets to squeeze the bulge down, nifty. Probably never have to do it now haha. I've only ever used the collets to nick old crimped in berdan primers out...

Originally Posted by StrikerNZ

Is that bulge not impending case-head separation?

I sectioned one of the cases to check this out and there is no sign of thinning. They have only been fired once.