Quote Originally Posted by Schnags21 View Post
Size the brass first with a 40 sw. then size with 357 sig die for shoulder only. Then normal process with a factory crimp die
^This is what I have done for years. Now that I use all Dillon dies on my 550, I don't need to do that any longer... For Lee dies, I suggest doing it.

For powder, I like Ramshot Silhouette, Power Pistol or Win231/HP38.