First off, I'm not a shot gun person, but I've acquired a 1995 Remington 870 Express Magnum which will take either 2 3/4" or 3" shells. I'm interested in installing a shorter barrel (20 - 22") for a house gun. With all of the variety of 870s made over the years are all 3" capable 870 barrels interchangeable and would therefore fit this shotgun?
