Has anyone used bullseye or similar powder with cow to expand straight wall cases? I'd like to blow 223 basic cases out to 357ar rimless. I have a 357 max contender I can swap the extractor out on. This is for a 357ar barrel I'm putting together for a friend.
I've blown 348 cases out to 450 Alaskan before, but never tried it with a straight wall case. If anyone has, how much bullseye would be appropriate?
They only need to expand about .004