We/I have several Gongs, I have 2 30" old Forage Harvester fly wheels hanging between trees at 1000 yards for center fire work including 50bmg, at 175 yards we have a 24" steel center rim from a Ford tractor with a plate welded over the center hole. in the woods around my house I have several 3/4 in steel gongs hanging between trees/posts. I like to weld the chains to the corners of the gong to hang. The 1000 yard gongs have 5/8 nylon rope to hang them. I think it lets them ring better.

I also have a couple of old 20 lp gas tanks hanging from trees, the won't take them for recycling till they have a hole in them so why not Hammer them good