Can't help with the rifle, but if you haven't found contact info yet you can go to the Frankonia Jagd website, maybe work out a way to ask them for rifle details.
https://www.frankonia.de/When I lived in Bavaria, I was able to shop at their Munich store... sort of like a cross between Abercrombie & Fitch, Griffin & Howe, and Sears-Roebuck.
-Chris
