The one that you like. Decide what you want to spend on one (don't forget that you'll need a scope and mounts, and accesories like a powder measure and powder flask ect.) and then look at guns in that price range and decide what you like. I read an article on .45cal vs .50 cal and if I was getting a new gun, I'd go with .45cal. Find a friend that already uses a muzzleloader and get them to help you find what you want, and get you started. good luck