Chuck, I really don't know the tools available and used in those periods, but if they could make beautiful guns like those, they must have had some "ideas" on honing, too. Some years ago I passed on a sideplate Optimus that had bores .020" oversized at or near the breech. I fear I was "too smart" for my own good. Actually on the first barrel bore report, especially, I am kind of amazed how close they were. May have been closer than my figures, but I only have a Skeet's gauge and -------well, I won't start that.