Trajectory question

[bang]

The OP said he was hitting 1" high at 50 yards. The absolute best thing to do is shoot it at different distances and find out where it hits and then determine the best zero distance off that data.
I'm going with a 75 yard zero. My RB load of 80 grains of 3f is 2" high at 50, and about 4" low at 100. Out to a 100 I can just hold a bit under center lungs and its going to do the job. I don't know what happens much after 100, I've limited myself to 100 yards or less.

Yeah with the limits of black powder and straight bores the range for as flat as possible is very short. After that you are using mortar sighting.

 

[45man]

Paper data does not work. You learn by shooting only with your gun. A RB will shoot farther then you can imagine but you need to shoot to learn the drop.