If you want an 8-9 lb. rifle, you'll need to go much lighter than a Rem Varmint contour. You'll probably be closer to 11 lbs. there, depending on the stock and scope used.
Personally I would go with something along the lines of a Remington Magnum Sporter at the most. A #2 Douglas or Remington Sporter would be just fine, too. The 20 caliber hole is going to add a little stiffness compared to a larger caliber, but it will also add weight, so no sense getting carried away on contour.
Neat idea, by the way. I thought about a fast twist 20 for a while, but never got one put together.
