German SD50 Markings

[Millsman]

Can anyone identify the maker from these markings please?

I assume the 2nd marking may be a filling factory with date.

John

 

[AE501]

Spotter has a sticky of German three letter manufacturer codes at the beginning of the forum 'identification' section.
I am led to believe that these codes ran from 1940 - 45 and that they were all lower case.
There was an earlier system that started in 1935, but only ran for a couple of years.
I would suggest that this later system started before 1940 and at first some of the bigger well established manufacturers
did their own thing and put their first initial in upper case. Apparently, some did so through the whole war.
If this is so, the filler would have been 'krl', Dynamit AG, Kruemmel, Bez - Koblenz, (formerly Alfred Nobel).
This was factory 13 in the earlier system.