I use 3/4 in light guns 7 lb or under 20 or 16 G. Have used 3/4 in light 12s but prefer 7/8. All SxS . Either load breaks clays fine if the gun is tight choked. Open choked or longer ranges it's not a lot of shot.

Pattern at expected range then choose . After looking at my 3/4 loads on paper went to 7/8 for preserve Quail and Chukars. 20 or 16g. Pheasants I want 1 oz in the 12. lot depends on how you hunt. Close or long shots

Boats