OK, one more tonight, easy on the eyes,
Never seen a rear site like that on any revolver before
I seem to recall that ladder style rear sights were once de rigueur with pistols optioned out for shoulder stocks. Going back to the pre-metallic cartridge days, detachable shoulder stocks were popular with a discerning group of shootists.
Certainly, early military applications, as in artillery, favored longer barrels and detachable stocks.
I’ve never heard of a Buntline employed by the military, but somehow, it just fits to match that long tube with the tall adjustable rear sight.
With magnum revolver velocities that sight elevation would be put the impact about 1500 yards down range. Old blackpowder loads still 700-800 yards