About all I do anymore with a shot gun is shoot 3 gun matches. I use an old police 870 with 18 inch smooth bore. (Not sights, just the single bead).
Most of what we shoot is bird shot, but are also required to shoot slugs and buck shot.
I reload for everything else, so why not a shot gun. I use a Mec 600 with a 1 oz charge bar for everything. Same powder charge, 1 oz of #8 shot, 1 oz of buckshot pellets (9 each .319 pellets at 48 grs each) and a 1 ounce slug I cast my self.
Kind of nice keeping the recoil the same across the course. Plus extremely cheap to shoot. I can keep all 9 pellets inside the A zone at 25 yards and I can hit a 8 inch gong at 50 yards.
I really don't see why I would need anything else. I do like keeping things cheap so I can shoot more and keep things consistent.
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071