Recently purchased 40-60 Winchester Hi-Wall manufactured in 1890 according to my Cody Letter. 
Purchased box of black powder shells from Buffalo Arms and proceeded to the range yesterday. I was not expecting great results as the barrel looked rough. First four shots had 2 and 2 less then 1 inch apart however the two groups were 6 inch apart. The more I shot the worse the spread became. Came home and really worked on cleaning the barrel, plugged the barrel multiple time and filled it with boiling water and was shocked with amount of dark thick water which drained out. The outcome is the bore is diffently pitted but a lot better shape than i expected.
Here's my reloading question to start with 19-20 grains of 4198 and .401 lubed (Baffalo Arms Bullet) or does have any experience and would like to make any suggestions?

Thank you