In focus of the sides of the frame, water table/action flats & barrel flats will aide in the ID. Gustloff Werke Waffenwerk examples aren't encountered every day. The concern began as Simson and was commandeered by the Nazis renaming it to Gustloff Werke Waffenwerk in 1939 so the scattergun would date to then. Pretty good overall story/overview here, http://en.wikipedia.org/wiki/Simson_(company) (copy and paste or select go) , but I haven't reviewed it word for word.

Kind Regards,

Raimey
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