S&W M41 I bought in 1973 used, it took me to All Navy Twice while on active duty and to All Army as a reserve back in the late 70's. I can't shoot like that anymore but I can still do this at 50 yards and I still use it for squirrel hunting.
I've got a cpl of Rugers that qualify...two .44 Special Flat Tops that'll do an inch and a half or better...but for real small groups, all the time...it's gotta be an older New Model Blackhawk with that long sight radius 6-1/2" barrel. I gave it to my son on his return from Afghanistan. Here are a cpl of pics. The blue masking tape pasters are from a 1" roll of tape....Rod
I dont know how accurate it really is, I've never sat down and shot at paper with any serious effort.
It will hit clay pidgeon chips on the 100 yard berm pretty regularly and it'll pop spent shotgun shells into the air that are laying on the ground well past the 25 yard berm in the 50 yard lane.
My eyes are much more limited than this Buckmark Hunter is, I've been giving real thought to adding a magnifying scope to see what it will really do.