Free: Contests & Raffles.
Do you know thee twist rate of your rifling?Some barrels are rifled for round balls.... some for conicals... etc. For accuracy, you really want to shoot what the barrel was designed for.
I had your exact rifle. 50yds with good eyesight. should be small groups, like almost one large hole groups. I installed a peep sight on mine at the time and the groups really shrunk. 90 grns GoexFFG , .530 ball and a .018 prelubed patch. Off the bench accuracy should be excellent. Off Hand, well thats up to the shooter. Great gun you got there.