Why would anyone use Krag brass to form Lee Navy cases?  The easy way is to get 220 Swift, turn off the rim and FL size.  Then seat the bullets out, because the necks are short. I did that with a sporter and it worked fine. The other way, with a really strong press, is to trim .30-06 brass back a bit and FL, probably with a forming die.  Takes lots of muscle, but produces safe, workable brass.