Somewhere around I have a pic of a target shot sometime back with the patched .77/44. Only 50 yards, but three shots in .6" ain't terrible offhand. It takes a wee bit of time to learn the craft and just a bit more to work up a load. I've yet to have a significant problem in developing loads for anything tried to date. Wrap up good bullets with the right load and it's pretty much a slam dunk.
Having learned the process and such, it takes about 5 minutes to cut enough patches to last a decade. About another hour to patch 50 bullets. Go have some whiskey while they dry, 10 minutes to lube and the rest of your time allocation goes to conventional loading mechanics. I run about 1600 fps out the muzzle with the .44 and a 300 grain bullet. The .45-70 uses 510 grains and gets close enough to 1800 fps to call it. It ain't a load you want to put in a Trapdoor Springfield.
Gibs, check your PM.
