7.92mm Head Stamp Identification?

[Patrick Chadwick]

You seem to have acquired the beginnings of a Spanish Civil War ammo collection!

All 3 bases with CH are from different series made by Kopp, Treuenbritzen. Google it!

The 37 could either be a number code for CH (C = 3, H = 7)* or a year.

*Sorry, got my fingers mixed up again! That doesn't seem to work (7th letter of alphabet is G).
Anyway, 4-37 seems a plausible date.

I wouldn't try to fire any of it! It's all pre-war stuff - pure collecting material - not for shooting!