Flintlock accuracy and need help finding load

[westrayer]

Try FFFg. I have been shooting it for 40 years. Burns cleaner and faster velocities.
I know you don't have any but maybe someone is close to you and can help you out with a bit to try.
Given the money you have in the rifle, it would be worth the money to try some. My T/C and Lyman 1-48 twist guns shoot better than that at 100.

 

[andy52]

You may have indicated this in one of your posts, but I'll ask anyway: Are you shooting freehand or off a rest?
As suggested I would give 3F a try at about 80 or 90 grains, 58 is about the cut-off point for me using 3F larger I use 2F. Most of my flinters a capable of better accuracy than you show on your targets off the bench.