It's been a while but I finally got around to making up some prototype dies and punches to test. This is to get the sizes and shapes right.
https://i.postimg.cc/xTqV2Fm8/20240106-115023.jpghttps://i.postimg.cc/TY6320t6/20240108-192215.jpg
https://i.postimg.cc/jjsx6SGk/20240108-192144.jpghttps://i.postimg.cc/CKY1vNf7/20240108-192318.jpg
And the results at 30m
https://i.postimg.cc/Gp1QqZQf/2024-0...b-HN-30m-1.jpg
This one is sized to take a CCI sub HN. The wax on the bullet stops it from sliding into the die which is a close fit. The idea is to hold the cartridge in alignment while the nose hollow is being opened up. There is no drive band expansion. The first test was simply to make sure they still shoot straight in my rifle and they do. I have made a second set that does expand the drive bands but I haven't tried shooting any yet. That one is intended for attempting to accurize rounds that don't shoot well. CCI shoot well in this rifle, that being my Voere, but don't perform well enough on the critters I shoot. They do seem to work better now. I only had one example but the damage made it look like the critter had been hit by something more powerful.
This particular one works best standing the loaded die on its nose like in the upright picture, then pressing the cartridge down onto the expander pin. I have an adjusting stopper to get the right stroke. Another die for expanding the drive bands works best with the case down so that the rim centers the case in a chamfer, otherwise the case is sloppy in it.
The case with the expanded nose just gets pushed out by the top punch.