Since you've talked to Corbin you probably know more about the die capabilities than I, but my last "visit" with them was several years back... It was a lot easier to swage soft lead than hard alloys. Spitzer shapes in lead require harder alloys to work to advantage; less bearing surface, higher velocity, stripping rifling, etc.

Most of my take on spitzer lead bullets is negative, but some have success. Another format for creating bore riders is paper patching. Works really well and speed isn't much of a problem. Have fun...

Dan
It was my intent to use J-4 jackets with soft lead cores for this experiment.
Jim