RE: low recoil 20ga slugs ?
stay away from high speed 20ga then.....I think normal 20ga slugs out of a decent weighted 20ga would be fine....
not sure they make light loads....check into that.
certainly a squishy recoil pad would help out a ton in felt recoil.....
having the gun fully loaded will add some weight so at the range......rather than just loading 1 at time....is 1 idea/suggestion