The original Army load was 70 grains with a 500-grain slug for rifles, but there also were Carbine loads (55 grains) in the same case and with lighter bullets: 405, 350. You can still buy it, but I don't like the idea of the jacketed bullets in an old barrel: the early ones were very soft (before 1893 or so).
All the old-time cartridges were named like that: .44-40-200, .38-40-200, .32-40-165, .44-77-386, .45-120-566 and my personal favourites: .450-85-480 for the Martini-Henry and .577-65-480 for the Snider (although British ammunition was never listed like this) et cetera.
It worked.
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