BTW, in a .31, you simply can't get enough powder into the thing to do much. Stuffed with 777, that 60 grain pill only pushed about 100 ft lbs, a number I get from my .22 mag NAA Black Widow. Pyrodex gives more like 60 ft lbs, about .22LR pistol ballistics. That little Remmy .31 is cute, but I'd much rather be armed with a .380, just sayin'.....
I don't have any experience with .36 calibers, never fired one over my Chronys, don't know how they compare (reference to the Navy). Beyond the fact that Bill Hickok was deadly with his Navys, I think I'd rather carry my little 20 ounce 2" .357 magnum Taurus 605 Poly. Hell, I think I'd rather carry my .38 Special Ultralite both for reasons of weight and concealment and raw ballistics. It pushes over 250 ft lbs with a +P 158 grain HP. I can't imagine a .36 Navy could in any way top that.
The closest IMHO that a cap and ball gun can come to a modern revolver is in .44 Caliber in big belt guns. The Walker is a monster, both in ballistics and in size. I can match that Walker's ballistics with my .357 magnum in a MUCH easier to carry gun.
These comparisons are fun, but if one is actually thinkin' of carrying a cap and ball concealed, well, I love all the modern choices these days.
I guess if I had to carry a cap and ball gun, it'd be the NAA Supercompanion loaded with 2.0 grain s Bullseye (by weight, but measured in a scoop) and the NAA 30 grain conical. That bullet is comparable to my NAA Black Widow in .22 mag pushing about 1100 fps and, at least it's concealable. Texas is not an open carry state.