Help: Found unidentified spring in chamber

[bill28465]

I am a newb to this site so I cannot use PM feature.
I bought a home defense 870 Express Magnum for my wife in the early nineties.
She shot it a few times but it normally sits loaded in a corner of our closet.
The serial number is 'AnnnnnnM' which I believe suggests that it was manufactured in March 1992.
Recently, I got it out and was attempting to clear ammo and ran into an issue which involved finding a 9/16 inch long by 3/8 inch diameter spring in the chamber. It does not appear to be the sear spring. Please see the embedded pictures. I want to ensure that the gun is safe to fire.
All comments are appreciated.

[MStarmer]

Hard to tell in the pic but it doesn't look like it came from the gun. If the gun has been sitting in a corner it's feasible that the spring dropped into the barrel. It's not feasible for a spring from the action or trigger group to make it into the chamber. Re-assemble and test for function. If you gun is going to sit in the closet for long periods (or at all for that matter) I would strongly consider something covering the muzzle.

[bill28465]

Hard to tell in the pic but it doesn't look like it came from the gun. If the gun has been sitting in a corner it's feasible that the spring dropped into the barrel. It's not feasible for a spring from the action or trigger group to make it into the chamber. Re-assemble and test for function. If you gun is going to sit in the closet for long periods (or at all for that matter) I would strongly consider something covering the muzzle.

Thanks for the feedback. The gun appears to cycle correctly and dry fires.
I am a member at a shooting club and can test fire it the next time I go to the range.

[Synchronizor]

I don't recognize that spring either. The only springs roughly that size in an 870 are the sear spring and hammer spring, but your trigger plate assembly clearly still has its sear spring in place, and a lot of other parts have to fall off before the hammer spring ever could.