I took apart my Mosin for a thorough cleaning and for some reason cannot reinstall the interrupter/ejector.  I have done this same procedure on my other Mosins and never encountered such a problem before.  The problem is that once the spring is seated in the dovetail and screwed it, the hole in the spring does not reach the "tab" on the interrupter.

Problem solved - had the interrupter on backwards.  

Glad ya got it figured out.

When taking something apart for the first time I always take a picture first, then I can use it to make sure everything's installed right.