I've heard the cautions about brass framed revolvers since the 1970's...and I wonder if the manufacturers may have improved a bit on the hardness and durability of the brass since then? Also the design of the revolver..., the open topped Colts vs. the 1858 Remington in a "Confederate" brass revolver, the Remington design is "stronger". '
Either way, you're not using them for self defense (I hope) nor for stopping a bear or mountain lion..., so no real reason to use, as mentioned, max loads. 15 - 20 grains depending on the caliber is more than enough.
I know a person who bought one of those conversion cylinders for the 1858 Remington, but he put it on a brass framed revolver...now the manufacturer says "don't do this", but he uses BP target reloads in .45 Colt, and figures if the pressure of 15 grains of 3Fg, plus corn meal filler to launch a 200 grain all lead bullet isn't enough to mess up the revolver in cap-n-ball mode...it's not enough to mess it up converted to .45 Colt. Now I wouldn't necessarily do that myself, nor recommend that anybody else do that..., however he's been shooting his revolver that way for years and no ill effects.
LD