Home Forums Hunting & Shooting Ask The Gunwriters Case Fire Forming Question

Forming 6 BR to 6 Dasher, jamming bullets 0.020". 16% of the case split the other 84% are perfect. Using 27gr of H4895 with 105gr HPBT Hornaday's.
Should I anneal the new Norma brass before forming or is there some other issue?

It's a cost of doing business. Seems a bit high - but 10% would be fairly typical.

If it were me, I'd run the BR's thru a tapered 7mm expander button and then thru the Dasher FL die to get a firm crush fit (secondary/false shoulder) and skip the bullet-kiss-to-control-headspace trick.

Ackley was NOT a big fan of the bullet jam thing to control headspace, but what the heck did he know about fireforming cases . . .

BTW - you never said what brand of cases or where the cases were splitting. I'm presuming a longitudinal crack near the shoulder/neck juncture.