I have a T/C New Englander in 50 cal, with the typical T/C 1:48 shallow groove rifling.
I'm assuming that your T/C has the same; if not, someone correct me.
The T/C Maxiballs shoot well, but at $12 or thereabouts for 20, unless you have more money than most guys, you won't want to shoot too many of these. Thus, guys typically don't practice much with Maxiball.
With roundball, in my rifle at least, the shallow groove rifling dictates that you don't charge too high, or the ball will "strip", thus ruining accuracy. Mine shoots Goex FFg, at 80 grains very well. (Actually, that's plenty for deer anyway.)
With blackpowder, and golfing, practice is a very important part of being good at it!