On shooting these old BP revolvers: I have done it for years, back
when there were plenty of them around for a few dollars. I still have an old Safety Hammer IJ from 1898, BP for sure, and I won't shoot it.
FWIW, it won't "explode" the old guns, but it will cause them to stretch and shoot loose due to the different burning characteristics of smokeless and black powders. I have found Iver Johnsons and H&R revolvers to be a lot tougher than most give them credit for, but why destroy an old veteran - keep it as a display gun and get something newer to shoot.
Also, DO NOT SHOOT ANY Forehand and Wadsworth, Meridan, Hopkins and Allen or other odd brand old top break revolver - they are not as strong as the IJ/H&R's and you will destroy them quickly. Most of these brands never made it into the smokless era, and they should be regarded as historic relics.
I have been told by "gunsmiths" that the old Smiths and old Merwin Hulberts were safe to shoot with smokeless, but I don't believe that, and would NOT recommend taking a chance on ruining an great old revolver.
Retire all old revolvers that were made before 1910 or so-they deserve a rest.
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