>>>Was not made in Suhl & not by August Wolf.<<<
Why? I think it was. On the barrel is seen a S in a rhombus, also a sign for Suhl. On my Drilling from the same time the letters AW and on the right barrel "August Wolf" and on the left barrel "Suhl". My uncle (born 1899) told me for a long time that AW stands for August Wolf.
On my Drilling 633, it stands for proofed June 1933, therefore I think 637 stands for proofed in June 1937.
The scripted letters W.K stands definitely for the "Rohrmacher", barrelmaker Wilhelm Kelber, in another thread you have also written by your own.

Zella St. Blasii don't exist since 1919, Zella-Mehlis is the name of this city since this time.
Albert Wilhelm Wolf (A.W.Wolf) is a gunmaker family existing up to this time, more than 100 years old.

Last edited by Ger; 04/30/16 01:54 AM.