Before 1935 George J. Hyde was a machinist and shop foreman at Griffin & Howe.
"Harry" Leonard, an expert shotgun and rifle stock maker, who had trained at James Purdey & Sons of London.
Hyde also did contract gunsmithing work for Roberts and Kimball in Woburn, Massachusetts.
Hyde was the chief gun designer for the Inland Division of General Motors (GM) during World War II.
Among others, he was the designer or co-designer of these guns: Hyde was married in Germany about 1917, to German-born Margaretta ("Greta") Levy (1895–1985).