I form .357 Wildey Magnum from .475 Wildey Magnum cases. Also .221 Fireball from .223 cases.
The .357 Wildey takes the use of two reforming dies to keep from trashing the brass. Though it is a heck of a lot of power. It shoots realy flat out of the 14 inch barrel of my Wildey Magnum. Brass for the .475 Wildey is expensive, and hard to come by so I do not shoot a whole lot with it. Though when I do it is a ton of fun to shoot.
No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.