"Mec, the pics of the old Remington are cool. Was FFg powder used because of the age of the revolver? Are you pointing out that maybe the originals had chambers close to or a little over the groove diameters in the barrels? I've wanted to know what originals had in the grooves and chambers for a long time. Especially the Colts: et al."
A guy sent me those because he knew I was intersted in the chamber diameter. So far as I know, he didn't measure the bore. Years before he had shot it with .454 or .451 ball and got a chain fire that un-nerved him. This time, he got some .457s and shot the targets you see. so far as revolvers go, the idea situation is that the chamber mouths should not be smaller than the largest portion of the bore. you want the bullet to be oversize or bore size when it enters so that you wont have to depend on obturation for a good seal or have the hot powder gasses escaping past an undersized bullet.
this is true for modern revolvers and I suspect represents the ideal for Percussion. However if the Revolver works and shoots accurately, I don't worry about it. My Uberti chambers and barrel throats all measure .450 either across the diameter or a pounded slug. There is the possiblity that I could be off .001 either way as I am no great shakes with a caliper. Nevertheless, all of these revolvers regularly turn in groups that would shame a lot of mid -20th century target revolvers. -- Not quite as often as a k 38, not evey time I whack away at a target, but regularly enough for me not to worry about whether or not I'm shooting an accurate revolver.
