I made a list of signatures, from the 76.2 mm ammunition elements sold from the USA to Russia. In particular, I am interested in the GH signature from a 76,2 mm projectile. I did not find it in the French list of producers.
A.C. Co. - American Cutlery Company, [cases and probably shells]
B.H. Co. - Bartlett-Hayward Company, Baltimore, Maryland [cases, fuzes]
B.S.C. Co. - Bethlehem Steel Company (Corporation) [cases, shrapnels]
R.&C.M. Co. - Recording & Computing Machine Company, Dayton-Ohio. [fuzes]
F.P.S. Co, E.A.C. - ?, [two signatures] [cases]
G C - ?? [cases]
GH / G H - ?? [shells]