I have a 1858 Parker Hale that slugged out at .582. Unless someone has a .580 hollow base for sale, I am looking at a RCBS Hodgdon North- South Skirmish mold. They range .580-.584. I have never used a flat base minie ball before. If any one has used them what size should I get and is a card required between the bullet and powder? Thanks and I hope I am on the correct forum.