Well, it seems that the guys in Karlsruhe were not too fussy about their head stamps representing the actualy company logo.
In the early years, we see the DM headstamps long after the ‘Deutsche Metallpatronenfabrik’ had become ‘DWM branch Karlsruhe’. On the other hand, we see DWM branded ammunition when the official company name has been changed to BKIW (Berlin-Karlsruhe Industriewerke or ‘Berkawerke’) in the 1920s. The pistols were also marked with the old script style DWM logo until the end (1930).
The same happens again in the 1960s when the name is changed to IWK (Industriewerke Karlsruhe) and later IWKA (Industriewerke Karlsruhe Augsburg).
Letterheads and other printed material also show a large diversity in styles, so that doesn’t help either.
For completeness sake, this is the DWM name change history (in short) until 1945:
4th of November, 1896: Formation of DWM (Deutsche Waffen- und Munitionsfabriken AG)
30th of May, 1922: DWM is renamed into BKIW (Berlin-Karlsruher Industriewerke).
29th of June, 1933: The company is named ‘Berlin-Karlsruhe Industriewerke vormals Deutsche Waffen- und Munitionsfabriken’.
30th of June, 1936: The company is renamed ‘Deutsche Waffen- und Munitionsfabriken AG’ (DWM)