I'm looking for suggestions. My RCBS shell holder (25ACP) has a tendency to allow the case to "extrude" into the priming clearences (central hole and recessed trough). Where might I find a solid base shell holder? The problem is particularly pronounced when forming cases from the 5.7x28FN case. I've tried lubing the cases and forming in several smaller steps, but I still lose too many cases. Ideas? Anyone?

Two thoughts. 1. Contact Lee and ask them to make you a special order shell holder that is not drilled through. 2. Have a welder TIG weld the hole shut and then level it off with an end mill.

Another alternative might be to use JB Weld to fill the recess. You could get it pretty flat to begin with and not have much work to do after it hardened to make it smooth and level. JB Weld is damn hard when it sets. Also, you wouldn't run the risk of damaging the heat treatment of the shellholder as you might with welding. And if it doesn't work, it was cheap and is reversable.