As I am quite concerned with the safety of shooting steel, I am posting some pics of the hanger system I made for my "close" targets - those up to 30 yards away. Farther targets will be held by shepherds hooks.
These pics are just from a model in my garage...but this set-up is fashioned after the Artzen tripods, which are commercially available. My brackets will mount on a wood frame to keep my costs down and safety up.
A 5/8" slot holds a 1/2" x 1 1/2" long carriage bolt and a nut holds the bolt tight to the plate. A second nut forces the steel to hang in the same way after every shot and the plate does not swing about wildly (like when held by a chain) - so its ready to be shot again with less risk for a ricochet (at least that's my logic - which I took from my target stand). Makes a good "ring" too!