This is my first and only Luger, a c. 1942 model which was reconditioned after the war with several replacement parts. I had had some jams with Blazer ammo, but the main problem seemed to be that the toggle (?) wasn't stripping a round from the mag every time. I decided to try different ammo--Fiocchi and Winchester. The problems merely got more frequent and more diverse. Failures to extract/eject, failures to load all the way into the chamber, failures to strip the next round from the mag, etc. I think that the ammo isn't fully cycling the toggle, so either the spring is too strong or the ammo too weak. I have gotten diametrically opposed advice on the ammo issue. Some say definitely use hot ammo, some say definitely do not. I will try a couple of mags of +P and see what happens. As it stands now, the Luger is no fun at all despite the very light trigger and the wonderful accuracy--WHEN THE THING WORKS!