Hi,
Sounds more like the loads lack enough power to correctly recycle the gun.
Similar jams occur when I feed 124gr ammo like GeCo in my Lugers. I use 115gr S&B, which is quite a spicy load and works the best for me. Since S&B is easier to obtain in Europe than Winchester, I tend to use S&B. In the USA, most forum member had excellent results with 115gr. Wallmart Winchester.
The combination of OAL, power, magazine and mainspring is critical on Lugers. Mess up one component and you're in trouble
I find that one magazine will function perfectly in one luger and will refuse to feed in another, so it's usually working through a combination of magazines and 9mm brands to find the right combo.
The MecGar for example, worked like a dream in a 1937 S/42, but refused to work in my 1913 Dutch. While the pre-1934 blued magazines work best in most of my Lugers, none of them like postwar DDR Haenel magazines.
You can also look for signs of wear on the bottom of the receiver and the tip of the hold-open. If there are visible scuffmarks on the holdopen and the bottom of the receiver, remove the holdopen latch and try to shoot without it to see if it feeds better. Also check the feeding ramp for possible snag points (as well as the top of the magazine).