The guide was whispering the distance to me. When he said "40 yards" I pulled the trigger.
I built the rifle back in the late 80s. It has a 38" swamped Getz barrel, Davis trigger and large Siler lock. I use hand knapped English flints.
I cast the 0.490" balls from wheel weights. Since they are harder than pure lead I had to drop from 0.018" patches to 0.015".
I used 90 grains of Swiss FFFg. Patches are 0.015" OxYoke lubed with mink oil tallow from Track of the Wolf. As for accuracy, check out the 50 yard target below. There are 10 shots in the target, though only 9 are visible. All these were with my hunting load, which chronographs at 2000 fps.
A fellow who founded Cast Performance Bullet Company put me on to using WW lead. He told me, "If you read the writings of Southerland, Forsyth, Clifton, Cody, and Ashley you'll see ALL of them recommended hardening the balls." He also told me, "I once shot 4 balls into 1 1/4" at 100 yards with a 54 cal FLINTLOCK over a rest, and I did it with WW balls."
I'm pretty pleased with the performance of my WW balls, though the elk has a different opinion.