The top lever is not engaged with the cross bolt lock.
I had one of these but don't clearly recall how the link up between the top lever and the cross bolt goes.
Many guns simply have an extension,,an arm, of the top lever poke thru a cut in the frame and insert itself in a slot in the cross bolt. Then the bolt slides back and forth as the lever is pivoted.

I'm thinking that this Walther instead had a separate part,,a ring, that sat under the top lever and around the spindle w/a stud in it that engages the top lever. Another portion of that ring has the necessary 'arm extension' on it that engages the cross bolt.
Why I remember it like that I don't know,,maybe I'm all wrong. Lately I have been!

Anyway,if the gun was reassembled w/o that 'ring'placed back in there, or any portion of that ring has broken,,,the cross bolt won't open (but the under lug bolt will operate).

The hammers appear down.
Try removing the top lever screw (looks like someones been at it already!)
I think the top lever will lift off leaving the spindle in place.
That 'ring should it still be there (and should it actually be the way I think this action operates!) will be right under neath the removed top lever.

If it's missing you should be able with a bit of angled attack w/a small punch or screw driver push the cross bolt out to the left. The slot to get at it is is at about the 11 oclock position in the rim recess of the where the top lever came out.

Once the cross bolt is out,,place the top lever back in the gun and screw it into place.
Open the top lever. It should still operate the under lug bolt and allow the gun to open.

,,,,and then again perhaps I'm all wrong and thinking of another long since gone project!.


I do kow the Walther SxS was a 1930's shotgun and was built with the assemblyline in mind, not hand fitting as was the norm up to then. But a precision gun resulted as with any Walther product. You'll find yr/date proof marks on the bbl flats.
Stamped internal parts,,all coil and torsion springs.
Very 'PPk, P38' like in it's construction inside. Markings are etched.
They did make a hand engraved variation and also offered ejectors for these.
Trigger guard and thumb safety was a cast plastic material over a metal reinforcement form to mimic black horn. Very brittle on the ones found around today.
Another option avail was interupting sears. Those guns will have an extra screw showing in the lower back corner of each the side of frame.
12 and 16 gauges IIRC.

Hope I helped and didn't just muddy up the water