This seems to be a favourite subject of mine lately and I have been acquiring a variety of
20mm FlaK 30 and Flak 38 kits in addition to the 20mm anti-tank rifles chambered for the 20X138B Solothurn cartridge. It seems that it was not just post war NATO countries that used this weapon but also many of the countries that were part of the Cold War nations affiliated with the Warsaw Pact. So the
20X138B Solothurn has a long history of military use and as such can be modeled for many nations and eras.
FlaK 30
Clicking on thumbnails will open up the Wikipedia page for the FlaK 2 cm 30/38
FlaK 38
I would also like to add this additional link devoted to the 20mm Flak and Kwk weapons called
FlaK 2cm which has a lot of interesting images of the various weapons chambered in 20mm that were in use during WW2. There is also a very nice gallery of images showing the many variations on how this ammunition was loaded into various size boxes ranging from one 5-round magazine to an ammunition box containing 100 rounds in individual cardboard tubes. It amazes me that much of this work was done by some very skilled carpenters and that work shows in the few surviving boxes seen on the various pages at
Flak 2cm