Back when men were men and sheep were nervous, Winchester offered all brass hulls in 8 and 10 gauge that were 4" long. Meant to be cut down to the proper length, these were used by various lunatics,er, ballistics researchers to move massive amounts of lead. The standard 10 gauge loads of the day came in 2 7/8" and used not much more than 1.25 oz of shot. One 8 gauge load from the Chesapeake market gunners used 2 3/8 oz of lead.
Some Brits used the long cases and Greener shotguns up to 4 gauge with no forcing cones for wildfowling, long range pass shooting on big birds, including swans. With ammo improving so much after the 1920s, the big loads died out over there and were outlawed here with the Conservation Act.
And yes, some of these were shoulder fired. Even with the slower black powders and velocities of the time, it must have been like taking Mike Tyson's best shot.