Looking for some advice here. I have a 500 Country Squire that I got as a teenager back in the 70's that I recently got back from my brother so I can hand it down to my son. I've broken it down, cleaned and oiled it, and took it out to test fire. For some reason I can't cycle the action after pulling the trigger unless I push the cycle/pump release button. This happens both when live and dry firing. I've taken it apart again and can't figure it out. I feeds and ejects fine and there are no other issues except for the pump problem. Anyone have any experience or advice on this? Thanks