I have to agree with JW. Round ball and patch shoots like a dream in most MLs. That's all my son uses and he puts down everything he shoots. And that's with an older CVA kit gun. Trick is to get out and experiment with different size patches and different powders.
I however do things a little different with my Thompson. I shoot patch and ball, but also a slightly heavier half round/conical ball. Got both impacting together at 50 yards using the same powder, but with different charges.
Another little trick to learn, is to load you rifle this season, and if not fired, not clear it until after season or next year and still have it go "BANG"............Art