Well, .45-70 was once common as .45 caliber , 70 grains of black powder, then the various bullet weights. I am using a 485gr NEI mold bullet with a 0.030" veggie wad over 70 grains of Swiss 1 1/2F powder. Havent Chronied it, but shoots like a dream and can hang with the Sharps until about 400yds then I run out of sight travel, and I am using the low Lyman up front and the Williams TK Peep onthe rear. If I go to smokeless, I use a reduced load and reach well out past 500, and can hit the Ram 7 out of 10, if I do my part.
Worst thing I find is case capacity with black vs bullet length/seating depth vs barrel throat. This is why I went to an NEI mold its a bore rider bullet, and lets me run a full load of black powder, minimal compression, even though I am using a drop tube, and wad. Still experimenting, but having fun all the while.
Buckeye, have you got the inserts? If not hit me up....