1993 Mitchell Luger

[ithacaartist]

Jim,
Presuming the he holdopen in the 08/90 (Sorry, I have yet to examine a Mitchell in person!) is the same as the original German, it is a little jigger that rests in a groove for it, inside the top right of the frame, parallel to the mag well's top opening.. Take off the top end of your Luger and observe from above what happens when an empty mag is inserted. Watch as the follower button contacts the bottom of the holdopen itself, and pivots it up. At the rear end of the holdopen part is a wedge shaped mass that is positioned by the offset in the holdopen piece to rise and fall in line with the path the breech block's bottom takes during cycling, as influenced by the follower button. Try moving the piece with your finger (no mag inserted) to see if it moves very freely, as it should. Make sure the holdopen's back end is able to rise to its fullest potential, presenting the most it can of its rising wedge to be exposed at the top of the frame, sticking up into the area where the breech block flies back and forward.
The pivot for the part may be sticky, one end or the other may be damaged or broken, or the thing may be bent. A weak mag spring may be only occasionally effective at its job in this system, as stated above; but you may have ruled out that aspect with your spring changes.
Google up Gerard Henrotin's "Luger Function", buy the e-book for the best $7.95 you may ever spend, when it comes to understanding how the "Luger System" works.

David Parker