I consider myself fortunate if I can remember that I found something related to the problem at hand.
Then I have to recall what the "something " was !
GT,
you are an inspiration to "never give up".
I can add that I have 3 or 4 of the Numrich drums, first one I bought on my own and found problems- GT and I did a long distance collaboration on that one and got it going.
I have a couple original drums that are quirky too, and would benefit from "treatment" - but won't get it- as I have others to shoot, and they should remain "original"
The next several were "GT" improved models, but of different iterations over several years. I still need to get one of the latest and "best" reworks!
I have one Navy luger, which I assembled from parts, that will shoot most any magazine or drum or ammo; others including matching pistols, just won't play well with
a drum! So if your "GT" drum doesn't work, it is quite likely the luger itself, or the ammo!