First, four inspection marks mean it was made after 1910 the leftmost inspection mark is made after the hardening of the receiver then it's marked after assembled and before the accuracy test then after it has passed the accuracy test at 50 meters, to the right the proof eagle after firing 2 over pressure rounds and 2 magazines in rapid fire. The revision mark means that somewhere along the process the piece was returned for improvements/repair.
The inspection marks are the initials of the family name of the inspectors under the crown.
Can't tell exactly who they were cause me and the gothic alphabet don't mix.
If it has the notch and it's marked 1917 it's probably an Erfurt. If it's DWM it started it's life as an artillery.