Info on DWM 1918 PLEASE!

[heers68]

Hello,first post here. I have had this Luger a few years bought from a fellow that didnt want his wife to get it in his divorce. Story goes that his father brought this and a Drilling home from WW2.
I have collected all types of German militaria for the last 30+ years but this is my only Luger. I know very little about the minute details on these so I will look forward to ANY and ALL info you learned fellows will share on this gun. I have been reading here for a while and you guys know your stuff!!
As you can see the serial is 3310 "I ". When does that narrow the production date to? All numbers match except for the mag and the left grip(this grip is WW2 marked inside,perhaps replaced during that time?)Bore is only fair/good with some darkness and pitting. Finish has allways seemed a bit too good and I wondered what you fellows thought on that. I have shot the pistol and it functions fine,with some sensitivity to the ammo fed it. A few jams on the round going into the chamber.
Curious on the value to see if I did OK at $650 about 6 years ago?Please feel free to give all info good or bad and I will be happy to ad more pics if needed! THANKS! Kevin.