RE: TC 56 cal smoothbore?
I once (and let me stress the word once) shot a two inch group at 44 steps I believe it was with my .62 caliber. I was shooting 80 grains of powder and a 324 grain .600 dia ball and patch. I was kind of excited. I was never able to repeat that group.
Good luck with your smoothbore. They are a lot of fun to shoot.