I don't think it's a question of advantages so much as feel and that elusive quality called cachet. And nostalgia. I heft my M1888 rod bayonet Springfield and I am at the foot of San Juan Hill on the morning of July 1, 1898
People are still buying single action revolvers, the number of black powder revolvers in existence today is probably 3x the number they had "back then".
IMHO 22LR single shots are the best way to train new shooters-of any age, the only real "advantage" I see to single shots would be for cartridges larger than say 458 Winchester Magnum/460 Weatherby where a bolt action would be too heavy, too bulky and too expensive.
People are still buying single action revolvers, the number of black powder revolvers in existence today is probably 3x the number they had "back then".
IMHO 22LR single shots are the best way to train new shooters-of any age, the only real "advantage" I see to single shots would be for cartridges larger than say 458 Winchester Magnum/460 Weatherby where a bolt action would be too heavy, too bulky and too expensive.