Pics of my cut down Mossberg. It started out as a 28" barrel with two beads. The middle bead is original, the front bead was moved back.
https://goo.gl/photos/RHaKuEW9Y9DmZ2Gd9
It could go shorter by an inch or a bit more but I like the way it looks with the rib and it shoots slugs quite well.
Bitter Bastard