1146 fps 28ga Lethal enough?

[Copper John]

I have been reloading a recipe from the Lyman book for 28a winchester AA hulls. I did some patterning yesterday and this load was by far the best out of my AYA choked skeet 1 and skeet 2 of the variety of shells I tried with #8 shot

My only concern is that this is a pretty light load at 1146fps with 8,300 psi.

Does that extra 54 fps do much in terms of knockdown power and decreased need for lead in factory shells? After reviewing my patterning yesterday I felt certain that I would use these reloads exclusively on grouse and woodcock this fall, I can break clays with them very consistently, but I want to be sure I am not going to be crippling birds with them.

The recipe is as follows:

11.5 grs Unique powder
win 209 primer
waa28hs wad (I'm using the clay buster version)
Win AA HS hull