my old 870, probably around 30yrs old now it sticks on ejecting a spent shell. It doesn't seem to be an issue of cleaning as i've cleaned it repeatedly. Any other thoughts on issues or corrections?

i haven't shot it a lot in recent years, but as a younger person it had A LOT of shells put thru it.

Could be the ejector.

Check both the ejector and extractor and make sure there is no pitting in the chamber

Some of the coated steel hulls stick in my gun. AA7 Winchester , STS Remington and express loads do good.

Check the magazine tube for buildup inside.

IME the Winchester Universals in the white boxes do not get along with the 870 unless you polish the chamber.

Wrap some 0000 steel wool around a worn out bore brush, put it on a short section of cleaning rod and chuck it in a drill, a spritz of gun oil on the steel wool and in the chamber, and run it back and forth in the chamber for a few minutes. This will work wonders, especially in the Express guns that are not polished as well as the Wingmasters.

A good cleaning of the magazine tube will help also.

The culprit most often ( in the last 5-10:years) is the cheap tin based hulls that expand too much when shot.

This. At the end of season I use 0000 steel wool wrapped around a 20 ga bore brush. Soak it good with WD40 and scrub. Cleans it up good and removes plastic, powder, etc quickly.

I know several people that use that for routine cleaning . The heat from the spinning steel wool gets all the plastic wad fouling, powder etc. out of the bore and polishes the bore. A buddy of mine does this and his unplated shotgun bore looks like it is chrome plated.

This ^^^^^