No you guys. Ralphy wants to know if you can just neck .30-06 brass down for use in a .270 Winchester. From what I've been told, yes. But you will likely need to turn the necks down, and maybe do some trimming. If you are in a pinch for brass, that would do. Use the Redding sizing wax for any necking down, and go slowly.
However, I have seen a Remington 7600 pump in .270 that, in the heat of battle had a magazine full of .308 put in place and fired one round. Nobody got hurt, but the rifle went for parts. It held together, but it feels funny to cycle the action. All's I had to say was "Better you than me."