Hi Tom, Not too awful many feet of that wire, would make thousands of those little pins? And if made like wire, they would have a very accurate inexhaustible supply at their disposal? I think the retaining pin hole in the knob was probably exactly the same as the pin, a slight to medium interference fit would be the result. So, what this leads me to believe, the pin fit snugly in the hole, and then was upset slightly from the top or bottom as I've seen signs of the pin touching the receiver when the toggle is flat on the receiver rail?... The oversize holes are probably the result of forced pin fit, with pins that were too hard, or someone trying to make it something it wasn't and drilled or reamed it to a more friendly size?... Hard to say, as for most of my Luger repair career, I've installed any pin I thought would fit well enough to not fail... I really didn't give it much analytical thought? Until now...
... best to all, til....lat'r....GT
BTW, the print calls for a 1.5MM pin, and that was probably the Germans 1/16" which at the time was probably in good supply for all types of manufacture? maybe even still is in Europe? Our forum family overseas would have to weigh in on this... Best, GT