Swamp...I know this is a little different gun than you are talking about, but I did take the action out of my Rem 7600 last year to "de-gunk" and clean the assembly.

I didn't touch a thing anywhere else in the gun. After putting it back together, it shot about 3" from where it previously did. Still consistant, but different. I simply clicked and re-shot and everything was fine.

Coincidence....I think not. LOL