I have 6 Remington 870 with a total of 8 factory barrels:
(4) Express guns with factory 18.5" police barrels
(1) Wingmaster with factory 28" barrel and factory defense barrel.
(1) Express with factory 18.5" barrel and factory 26" barrel.
Every single one has problems with Federal Walmart steel hulled ammo. These same guns run perfect with Winchester AA brass based shells. Three of the barrels have had the chambers recut and polished by a Remington repair center. I have done the AIPPI steel wool polish multiple times to each.
ALL STICK HAVE EXTRACTION PROBLEMS with steel hulled shells. Some barrels are worse than others. Typical failure rates are 5% to 25% depending on the barrel. My Benellis eat this ammo like candy.
I read the following post and did what the author recommended to all my barrels. The problem is solved. No extraction problems. Basically, the fools at Remington don't seem to mind shipping barrels with toolmarks that the steel rim catches on outside the chamber when it expands after firing. If you have a 870 with extraction problems, take a look at the ridges just outside the chamber. Steel shelled hull expanding into a steel barrel with ridges = stuck shell.
It is not the chamber. It is outside the chamber. Here is a post that explains the fix. It is not my post. I just did what it said and the problem was solved.