raybass: Building on a M70, you have to watch everything to avoid ending up with something heavier than you want it.
In 270 I would go with a #1 Krieger (which means CM,which does not bother me),or a "0" contour FW Brux for barrel. I spoke with Brux yesterday and if you are very specific they will contour a barrel the way you want.
On bottom metal I would look around and see what one piece aluminum units are available.....this knocks off ounces over a steel unit.
I have two back here,both on pre 64 actions.One has the original factory barrel,aluminum floorplate,and Compact Edge stock,Leupold base and rings,and weighs a bit under 7.5# with a 2.5-8 on board.
The other has a Krieger #1 CM finished at 22",aluminum BM,DD bases and rings,and a Brown precision Pound'r stock.With a 4X leupold it weighs 6.9#'s.
Lighter bases and rings would knock off some weight.
You could go with a slightly longer and heavier #2 contour,but will add a bit of weight.Depends how you want to roll.
