About 5 years ago I bought a used .40 caliber GM round ball barrel from a member here for my TC Hawken. Put it in the closet. Now I would like to shoot it. Could someone give me a guess as to the size ball and type and thickness of patches to order to try? I have shot little blackpowder, mostly with minis in my .50. I have to order my stuff so I need a starting point. I will be using a substitute powder, not real black.