RE: 7mm Remington Mag - QUESTION!
There's really no need for magnum loads for any whitetail on Earth... Give the 140 grain Remington Managed Recoil rounds a try. They dial the 7mm Mag down to about a 7mm-08 power level, and should be very effective on deer. I used one last weekend and it dropped a 200 lb. boar in its tracks.