I still have a few Activ Steel loads, they were the very best for shooting out in salt water, you never had to worry about the metal rusting. Their target ammo was top notch with hard shot in even their cheapest loads.
Herter's had two lines of all plastic shells, one with a crimp end and one with a plastic overshot wad. Killed more than a feww ducks with them but that was back in the lead days
I did allot of target shooting with Wanda shells, they were clear plastic with a overshot card. They were kind of neat you could see the shot, wad and powder through the plastic.
I'd love to see some company bring back an all plastic shell for saltwater hunting.
AWS