I don't know how those "chart" figures are derived, but they can only be an arbitrary guide. A 1 1/8 oz. load @ 1250 fps from a 7 lb. sxs is going to have a lot more free recoil than the same load from an 8 lb. gas-operated semi-auto. Just saying...
JR


Be strong, be of good courage.
God bless America, long live the Republic.