I do not reload shotguns for steel. I use Hevi-Metal 20ga 1oz #3 shot. I am finding myself using the 20ga more than my 12ga due to weight of gun, recoil, and quick handling. I am running a Benelli M2 in both the 12 and 20ga for waterfowl.
The Hevi X 20 gauge shells were amazing for my son last week
in Arkansas. He was able to shoot his limit each day cleanly.
I also want to suggest that if anyone is looking for a shorter
stock shotgun for a youth hunter or lady hunter check out
the Mossbery SA-20's.