Hi Duke,
The bolt face looks like it's been ground down, probably at at an angle making it impossible to pick up rds from the magazine. This was common practice for the non-firing models. It looks like there are drilled holes through the barrel nut running into the chamber. Again, common on the non firing models.
The cartridges aren't correct for the MP40. They wouldn't fire in a manner that'd produce any blowback. Probably from one of the early non-blowback 9mm pistols.
I hope that helps.
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Cerwyn
Hobby collector of Replica model guns and Militaria.
also member of Living History Reenactment Groups.