I built a 45 cal. Longrifle 45 years ago. I only hunted once with it in all that time and never killed a deer with it. I built a nice .54 flintlock soon after this rifle, and have used it for most of 44 years.
I got the old rifle out a few weeks ago and worked out a load of 70 grains Old Eynsford and a .440 roundball with .017” denim patch, lube with bear oil.
I hunted with the rifle for the Illinois muzzleloader season without getting a shot. However, the county my hunting property is at, has a bonus late winter season this year. Any unused permit is good. I had loaded the gun in early December and left it loaded until I shot on the 26th. Went off perfectly.
The deer was about 50 yards. At the shot, it ran hard for another 50 and fell on a gravel drive. No dragging required! The ball destroyed both lungs and stopped against the hide on the offside shoulder. It flattened to over .650”.