John Moss, I am in the process off adding those specific dates in John Korts article. Would the below be an appropriate change?
Early Differences between the .44 W.C.F. and .44-40 cartridges
Until 1885, both cartridges were dimensionally the same and both used a 200 gr. bullet over 40 grains of black powder. However, from [January 2] 1886 until [April 7] 1904, the .44-40 cartridge would carry a heavier 217 gr. bullet at 1,190 f.p.s. The .44 W.C.F. cartridge on the other hand, would continue to be offered with the 200 gr. bullet at a slightly faster 1,245 f.p.s. Both Winchester and U.M.C. loaded both versions of these cartridges with their different bullet weights. (Note the drop in catalog velocity from 1875……no doubt due to the improvement in chronographs during that period of time.)
In [April 7] 1904, U.M.C. changed the bullet weight of their .44-40 cartridge back to 200 grs. but Winchester continued to offer the 217gr. bullet in their .44-40 cartridge for several more years until they also standardized on the 200 gr. bullet for both the .44 W.C.F. and .44-40 cartridges.