Next german code from IIWW is “drv”
This code is connected with ammunition factory in Częstochowa (Tschenstochau)
drv - Hasag, Eisen- u. Metallwerke GmbH, Tschenstochau
We can find this code on ammunition:
13x64B MG131
(municion.org)
(reibert.info)
20x82 MG151
