Cal 320 Shot

Here’s a 320 Short Shot. I assume the “D” is Gustav Genschow.
Any thoughts on when it was made?

Cal%20320%20D%20HS

Thanks Paul

Used from after the 1909 Erfurt Conference until after the adoption of the “GECO” trademark was used in headstamps c1922.

This illustration is found in Genschow catalogs from c. 1924 to 1929.

320

WBD and Fede, thanks for the replies.

Paul