What I understand he was a foreman of the stock shop and a master engraver himself.
That was at Newton Arms. And I'm not sure about the "master engraver".. haven't seen a source for that. Engraver, yes. Not sure what makes an engraver a "master engraver"?
I found that a John Spitler was registered as a Savage Arms toolmaker in 1918. We all know how those toolmakers are.