That famos gap seams to be a lot of trouble, I wished they quit using pot metal for the underlug besides the underlug has reduced end bearing for the pin..
That stuff just dont stand up with high intensity cartridges. How much does a little piece of hardend steel cost. This is a disgrace.
The simple repeatble fix is Devcon Steel putty in the hinge pin seat. One of my rifles shoots well with this fix the other has the same fix but has not shot yet.