8s will do 90% of what I need done on doves, quail and woodcock. 7 1/2s excel in the late season on older, tougher and high flying birds. Same deal for clay birds...........use the 7 1/2s on the really long targets, 8s on the rest. That said, I get very reliable, hard breaks on clays at 60 yards with 8s out of a .020" choke, at 1150 fps mv. Density is just as important as retained energy. Three 8s may kill a bird, or break a clay when two 7 1/2s might not.
I'd never feel the need for any load above 1175 fps. on any game bird you listed (I don't hunt grouse). The faster a load leaves the muzzle the faster it sheds velocity. There's not near as much difference in velocity and energy at 30+ yards as there is at the muzzle. The only shotgun load I want high speed is steel, for ducks.
SRH
