Luger rear sight problem(?)

[sheepherder]

Originally Posted by PRD1

Another feature I didn't mention earlier is that there is a 'notch' and small flat in the front of the receiver ring, leaving the barrel shoulder standing above the receiver ring at that point: I can easily imagine that cut being a clearance/seat for the back of the artillery rear sight.

That's exactly what it is.

Originally Posted by PRD1

As I don't have a reference on Lugers, is there any place I could view photos of the various toggle assemblies?

I only have a couple...maybe 5...

Others here have whole collections of toggle trains...

But here's an Erfurt Artillery toggle compared to an S/42 Army toggle...