RE: Remington 1100 Question
This from the Remington website on the steel shot barrels.
‡NOTE: Model 1100 Steel Shot Barrels are designed for use with 2-3/4" or 3" Magnum steel or lead shot shells when used on Magnum receivers and 2-3/4" or 3" Magnum steel or 2-3/4" lead shotshells when used on non-Magnum receivers.
I'm not convinced that a non magnum receiver will have the clearance to eject the 3" shell even though the barrel itself is designed for up to a 3" shell. I know of several pump shotguns with a 2.75" receiver that can be fitted with a 3" capable barrel but are still limited to being allowed to shoot 2.75" shells.
Either way I would call Remington to make sure.