I was reading an article about handloading the .44 Special last night, and the writer questioned whether the .44 Special was ever a blackpowder round, having been introduced in 1906~1907. His comment was that smokeless powder handgun rounds were already in production by then.
From such authorities as White & Munhall and Gen. Julian Hatcher, we learn that the .44 Special was a lengthened .44 Russian round, to hold three more grains of blackpowder, to boost performance. Blackpowder in 1906?
Bear in mind that smokeless powder did not work well in revolvers of the day. Unlike other arms, the cartridge case head is not rigidly supported by a breech block in a revoolver. Clearance must be allowed between the case head and standing breech to permit free rotation of the cylinder. Otherwise, binding occurs. This was further complicated by the extra allowance for blackpowder fouling. When original blackpowder cartridges were loaded with smokeless powder, the extra quick high pressure generated slammed the case back against the standing breech, tying up rotation.
So, for awhile at least, REVOLVER cartridges continued to be designed around blackpowder. As an interim, semi-smokeless powders were developed to produce less flash and smoke and fouling than blackpowder, but less pressure than smokeless powder. Not until about the beginning of WW I did smokeless powder become universal.
Examine old cartridges, paying attention to the primers. Copper primers indicated the round is loaded with blackpowder, brass primers indicate semi-smokeless (Les Smoke, for example) powder, while nickel plated indicate smokeless. This holds true for old rounds, as the current standards abandon this practice. The lack of a groove ahead of the rim will indicate an older round.
The .44 Special made its debut in the Smith & Wesson New Century, or Triple Lock revolver.