I have an Activ data book at home, and can supply some load data.
Activ hulls had about the highest capacity of any hull ever made, typically requiring the use of Activ wads for the lighter loads (their wads being longer, to consume some of the internal volume).
I still have lots of their 20ga hulls, but have not reloaded them in yrs.
They are good hulls, and their factory ammo was good. Not sure why they went away.