The headstamp lists M&W Soemmerda only, which was Munition–und Waffenfabrik in Sömmerda in Thuringia (Germany). I am still looking for any additional information on this cartridge. It is listed in the ECRA database with code 07047BBC040. The specimen listed here is different from the one listed on the ECRA database, even though from the same original source, which means that there might be more, even a box somewhere?
