[Thor]

you ought to be able to remove the mag, then put in an empty one to fully lock back the toggle? Maybe I am missing something, if so, ...nevermind!
I reread the post and saw you couldnt do it. The extractor must have a good lip to catch the round edge, and it must be able to freely rock back and forth with thumb pressure to get unimpeded movement and it needs a strong spring to grab onto the round. Does it feed manually and eject manually okay? (Caution with loaded ammo) I have dummy rounds I loaded for this purpose, they are without powder and primer so they are inert, just the bullet and case. You can also remove the firing pin before checking for manual feeding and ejecting with loaded ammo. It may not exactly duplicate what is happening with the cycle, but it MIGHT indicate which of the three items (lip, movement, spring strength) is a problem. Be worth a try.