wvbias,
I've never shot flintlock or muzzle loaders but I have seen them being used at various ranges, and I dont think 3in shot groups are that bad. I cant really remember if they were shooting 50yd targets or 100yd targets though.
Shooting shot groups at 50yds open sights that a dime can cover are good shot groups for sure.
Anyone ever done match shooting? I had a couple friends who did, and it sounded like a lot of fun.