German 8cm smooth-bore ammunition (drawings)

Did these items see a great deal of use? Was this a technical dead-end or has the principle been used since?

Happy collecting, Peter

Peter, these were the two types of rounds (HE-Frag and HEAT) for the PAW 600 which came very late in war. Supposedly 81 weapons were fielded and used.
The Czechs refined the system and put it into service after 1945. Here what they been using:

Maybe there were more systems basing on this principle but I have no idea where to look for right now.
Slowly I am getting the impression that my documents became worthless since I do not know where to find something once I need it.

The German shells are rare. The Czech shells are not.

Despite that you are correct I owned more German than Czech ones in my life.