I never understood why Colt continued to bore through their cylinders when no longer using a heeled bullet? It must have affected accuracy and maybe muzzle velocity as well? I find evidence that Colt introduced a stepped chamber after the Model 1901, assuming in the 1903, but have never inspected this model.
The Pitman Notes are interesting for this caliber's use in the military. Colt apparently kept their bore large, a carryover from the heeled bullet design until the introduction of the Model 1903 that was ordered with a reduced bore diameter to improve accuracy. The author notes cartridge change from black powder to smokeless in 1901.
It is also interesting to note that General Pitman never mentioned the S&W Model 1899 in the 1891 - 1911 section. He did, however, do a detailed discussion on the 45 Colt and the 45 Schofield models. As for how S&W got a contract for the 1899 and 1902 may be well known by Charles Pate, but is not covered in detail in any reference I have. Only Roy's comments that "one thousand of this model were issued to the Navy and 1,000 to the Army. The Navy models were ordered June 25, 1900." It also goes on to state that "the Army model was ordered February 18, 1901."
Maybe Charles can find this thread and comment further as to how the company obtained contracts from the Army and Navy in the first place?