Fredo,
As to what type/variation your luger is :
1. I think, based on the V. Bobba tables I posted above, your Model 1900/06 W+F Swiss Bern luger is a 2nd. series, 1st. variation.
2. The fact that your frame interior is blue, makes it so.
3. Yours still has the stepped breechblock.
4. Your early trigger side plate is the only odd thing about your luger. Usually these would have the more simple side plate with the "island" that runs all the way to the top edge...but your side-plate is properly stamped with your guns' serial number...so it more than liekely left the Bern factory as so...
Bobba says after serial number 27501...the more simple trigger side plate occurred...but your serial # 27958 certainly proves him wrong in this aspect.
My guess is the day Bern was making your luger in 1928 they had on hand both the old style and the new style trigger side plates available and decided to use an old style plate on your pistol to use up existing inventory and not waste the extra gun parts in the factory...just a WAG, though...(WAG = wild ass guess...).
Regards,
Pete... <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />