Gunsmithing Mossberg 500 locking on fired shell

[Apothus]

I have a model 500 that has been serving me faithfully for 16 years now. Lately though I've been noticing that after certain firings, the pump locks up and won't remove the spent shell until i really pull on it.

If I push the slide release on a loaded shell it releases smooth as butter, and if I pull the trigger on an empty chamber and pump it works just fine. So it only locks up on a fired shell, and not all the time.

I cleaned it recently but didn't scrub it. Could the chamber be fouled still? Was thinking of chucking up a bronze brush on a section of cleaning rod in a drill and scrubbing really good.

Any thoughts or recommendations?

 

[GH41]

My bet is a dirty chamber and maybe cheap shells and a fouled chamber. Chuck up your brush and wrap some steel wool around it. You want it so tight you can barely get it in the chamber. Add a dash of #9 and spin away.

 

[callen3615]

Just dirty, clean the chamber. What shells were you shooting? Winchester always gets mine sticky.

 

[Apothus]

Federal target/game load 7 and 1/2s and Winchester #4s