Georg roth, jiri roth on shotshells

First I like to add the timeframe DocAv listed.
Thanks for that!

Hope I did it right.

Now I like to show some shotshells.

First GR monogram up to 1919
Second Jiri Roth up to the early 30’s
Then the (M) headstamp. In 1934

Where does the G. Roth A.G. Wien fit??
And are there shotshells with the Z headstamp??
Any information is welcome.

Regards René