They are Cheddites (come in gray & red). Pretty much the same as Fiocchi's, too. As long as they're not max loads, I'll use Fiocchi or Cheddite data as you'll see there's little differance. Federal Goldmedal, W-W,& Remington SP w/ a separate basewad (Riefenhauser-type) are in the same category.
Steel loads are available from Ballistic Products(good source for wads espec for steel shot) and Alliant for Steel powder( These loads tend to be max so don't change any components).
