FWIW, on pp 240 of
The Standard Catalog of Civil War Firearms by John F. Graf, inspector "H.G.S." is listed as "unknown", with the mark found also on early Starr Carbines - which suggests to me that "H.G.S." was a Gov't arsenal inspector or sub-inspector.
http://books.google.com/books?id=GXC...h.g.s.&f=false
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