John:

The one you missed out:

11 lb double rifle
.470 NE
500 gr bullet
105grs powder charge
Velocity 2125 ft/sec

Recoil Energy of 70 foot pounds, and Recoil Velocity of 20 fps.

Now in a ten pound rifle

10 lb double rifle
.470 NE
500 gr bullet
105grs powder charge
Velocity 2125 ft/sec

Recoil Energy of 77 foot pounds, and Recoil Velocity of 22 fps.