I have a matching and mechanically perfect, albeit bloodstained,
1937 HK Luger that I've been trying to set up as a shooter. So far, reliability has eluded me, notwithstanding the use of Haenel-Schmeisser and MecGar magazines and Wolff springs in all weights, mostly in the form of stovepipes and failures to feed. I would be very grateful for any tuning tips or pointers to gunsmithing literature.