Thanks Timber, I hate to waste the money on components to get my undersized cases back to chamber dimension. My gun shot great with new Remington brass, because it was the proper size. I now have 300 cases of Bertram that is the same size as the Remington and I think I will just neck size it before shooting and see how it goes. I did try loading some unsized Bertram and found that the neck tension wasn't tight enough and my 300 gr OTM was pulling out with the sizing stem.
Dave, most likely you will have to fire form it to get to your exact chamber dimension anyway. Once fire formed and properly sized your velocity will be around 30 fps faster than new non fire formed brass.