Sad thing is there are likely quite a few DDR/GDR (German/English version) guys still around that could at least explain what was done exactly and why to those 1950s East German re-works. I would be curious as to the standards for barrel replacement, hard to believe that many Luger barrels were beyond serviceable to warrant large scale re-barreling.
Many questions, few answers, just really cool dicked-with Lugers and speculation
