[ithacaartist]

The very first thing that I'd attend to would be getting ithat upper into proper position when it's in battery. Starting out from the right place is a good thing, and may improve ejection. Since Lugers are machines with inter-relating balances--ammo, recoil spring, mag spring, and all the different weights of the components that go whanging around when it's fired-- I would not dismiss the possibility out-of-hand. If your lug is deficient, a weld to replace the errant material would be a simple matter. It might not hurt to remove the locking bolt for examination/comparison with a standard one.