Stevie,
My byf 41 exhibits the same behavior about the toggle being able to be pulled back and up until and remains there, but does not exhibit the jamming that yours does.
In those cases where the toggle can be pulled back in this manner and it remains up, I have determined long ago that this is the point where the sear notches engage and the slight resistance difference between the recoild mainspring and the firing pin spring are what cause the toggle to remain up/back.
I would not consider this to be a cause of your jamming... but would believe it to be as a result of the magazines that you own and their compatibility with the your frame...
Find the mag that WORKS and use it exclusively in that Luger... once you have the functioning cured with the right magazine... then you can play with fitting another aftermarket magazine until it also functions... it is all a matter of feed lips AND smoothness of follower operation AND magazine spring smoothness and strength AND the appropriate position for the man button catch to hold THAT particular magazine... AND smoothness of all the moving parts in the gun, AND various spring strengths, AND proper lubrication....
Fix all those variables in the appropriate way and you won't have any more jamming
