You can use the same data for 12 and 20 ga HS. In both you will get slightly less velocity (probably pressure, too) vs comp formed version. WW redesigned the AA20 wad for the new hull. If you want 7/8 oz in the new hull use their wad.
Larry's point about the 28 bears emphasis. Most early lots of HS 28s should be about used up by now. Simplest approach is to steer clear of them. The latest version is excellent. The single best .410 hull we have ever had.....yes, I said that......is the new HS version. It gives well over 10 reloads. Actually, I've gotten 12 to 15 loadings. The 28 and .410 HS hulls require new-style wads designed for straight walled hulls. As it happens Fed and Rem .410 wads work perfectly in the .410 HS hulls.
Sam
