There is very little to go on here, the photo seems to have been taken in the Gothemburg area, possibly at a competition of some sort.
I am no gun expert, I don’t know what kind of SMG the man is holding.
I just found this photo interesting as it is unusual to see a person not in uniform holding any military weapon in Sweden.
The photo is in the public domain.
Cross posting my comment
Im no gun wizard, but that looks to my untrained eye to be a PPD-40 with a box magazine instead of a drum?
_https://en.wikipedia.org/wiki/PPD-40?wprov=sfti1_
Im assuming its a PPD and not PPSh because of the … back bit by his eye above the stock (not the sights)
It kinda looks more like a Suomi SMG, the stock now that I have had some time to look closer at it
Very interesting, thanks!
Is one a copy of the other, or perhaps both based on the same weapon? You might find this interesting
https://www.jaegerplatoon.net/MACHINEPISTOLS2.htm
I think I have found it!
I think it is a “Kpist m/37-39”
https://smallarmsreview.com/swedish-quality-the-kpist-m-37-and-m-37-39-submachine-guns/
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