A Learning Experience...

[ViggoG]

Wes & Ron,
I would respectfully suggest that High precision mass production is not a Post WW-2 concept.
Nor is it a German or American doing, The Swiss have for many years prior to the First Borshardt Pistol, Manufactured Gears, Cams, Springs, and Precision Screws that were so small as to be almost lost to un aided visual inspection.
And there was no try and fit procedure.
There was a family home community business co-op process whereby one family made gears, another springs, another Watch Faces, another Jewel Bearing Assemblies and others assembled the various parts and calibrated the product.
No doubt The Fine German Gunsmith Machinests took heed of these production practices and were perfectly capable of many things that have been forgotten by all but those who still remain that have used the machinery of that era, and recognised that we cannot say that it was done this way or that way with any confidence.
What we must recognise is that the Head space had to be reamed and set and Extractor and loading ramp cuts were needed before the "locking up" of the "Barrel - Fork Assembly" was completed.
So at this late date, we can just guess how they accomplished this and the many other facets of the production process.
ViggoG