Eabco is good to deal with. I have bought a lot of stuff from them. Another good place is Match Grade Machine. I like MGM's barrels. If I were you I would call them. They will take the time to answer all your questions, and their advise is first rate. I have a few MGM barrels, and they are first class.

Of the three cartridge's you listed, I would pick the 270 over the other two. But then I would probably go with the 30-06. Oh that is right, I did. Tom.