score:7
Since the chambering is 41 Colt, I would agree that the black powder cartridges would be appropriate. The 41 Colt was created in 1877, and as such the original specifications called for black powder loads.
The book The Modern American Pistol and Revolver, published in 1888, lists several loads for 41s:
where the 'powder' listing is grains of black powder.
Since the firearm came out right at the time of the earliest smokeless powder production, which was originally used in military weapons, it is likely the first rounds fired through it were black powder rounds.
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