I've seen it commonly noted that a .30 cal projectile be sized down to .298" for wrapping. I have a lathe, and while my skills are not stellar, "they ain't bad either". I made a simple sizing die, it measures .299". I'm casting pure lead 150 grain (lee FN) for my 336. I ran a few through my Rockchucker and die, and it wasn't easy. I did in fact wipe the drive bands off, and leave a ring of lead around my pusher rod.
I know buckshot makes a sizing die, as I've seen it mentioned in more than one thread. I now suspect however that this much reduction should be done in stages, or is tapered or some such other black magic...
Any one care in enlighten me?