Hi
I have never worked on any Erfurts, those are very uncommon here. And besides I prefer to build are shooters form Mauser shooters.
The army acceptence drawings that I have does not state any differances betwen Erfurts and DWM.
I do very much doubht that this was made on purpose.
Maybe what could have happend is that a previus owner have lost one or two gripscrews and turned out new, and maybe altered the Withworth tread in the gun to UNC.
Just a guess, I don't know.
Another thing about gripscrews.
I orderd years ago gripscrews from the Gun parts corporation and got some new manufactured ****.
The screwheads was not curved but flat with the corners in a degree. And the thread did not fit to my DWM Luger, or any other luger i have tried them on.
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