I've developed a lot more, and better, information on Leonard. I'll need to rewrite his history someday.
Here is what I published on him.
Leonard & Hyde:
Tracking Samuel A. Leonard has been like looking for an arctic fox in a snowstorm. I know he existed but I just cannot get a complete picture of him. Sometime before 1928 Leonard left his job as head stocker for Purdey’s of London and emigrated to New York City.
Before 1935 George J. Hyde, who was the shop foreman and metal man at Griffin & Howe quit G&H and went into business for himself. Leonard teamed up with Hyde and their rifles are marked “No. XXX Leonard & Hyde New York” on the barrel. In May of 1935 Ned Roberts and his father-in-law W.G.C. Kimball went into business together as “Roberts and Kimball” in Woburn, Massachusetts. Their idea was to make high-quality sporting and varmint rifles on Mauser actions in the then popular cartridge that bears Roberts’ name, the .257 Roberts. Metal work on these Roberts & Kimball guns was done by Hyde and the stocking was done by Leonard. Some information suggests that Leonard and Hyde did not relocate to Massachusetts but that the work was sent to them in New York City. Roberts & Kimball company lasted less than a year and their rifles are not found very often. As far as I know the barrels are marked “Roberts & Kimball”. Before or after this business failed Leonard made “Best” quality sidelock double barrel shotguns and sporting rifles under his own name. The illustrated Leonard-Springfield sporter is marked “No. 219 S. A. Leonard New York". In outward appearance this rifle looks like a G&H as far as all the refinements on the metal. It has the matted receiver top, thumb print on the floorplate, finely checkered trigger, ramp front and barrel band sling swivel. I have no doubt that the metal work was done by Hyde. One known Leonard shotgun is marked No. 1945. What these numbers stand for I have no idea, but I do know that Leonard did not make 219 guns, much less 1,945 of them. The quality of workmanship on all of Leonard’s is as good as Griffin & Howe’s. After the Roberts & Kimball business failure I have found nothing more about Mr. Leonard. Did he return to England, as so many others did at the outbreak of trouble with Germany? Whenever I think that the search is hopeless, I think of the length of time I spent trying to locate a relative of the late master engraver R.J. Kornbrath. After getting nowhere, my good friend John said “Why don’t you have a talk with his grandson. He lives over by you in South Anchorage." We may never know where Leonard went, but we do know what he left behind; Some beautifully made guns.