Receiver Measurements

[Mauser720]

When fake crests or dates are put on Luger receivers, I suspect that it would be necessary to remove the original date or crest, etc.

And this would involve the removal of some of the metal from the original surface of the top of the receiver where the barrel is screwed in. Thus the modified surface should result in a measurement that is slightly less than what is the case for a factory original piece.

I have seen a few photographs of Lugers which appear to have a slightly flat receiver surface which may have been the result of a minute amount of metal removal.

Precise measurements could be done, for example, by a machinist with a micrometer, measuring the distance from the bottom of the frame to the top "dead center" of the receiver.

Has anyone ever tried taking precise measurements this way?