If money is a consideration, then you want to stay away from factory ammo for the 470NE (i.e. Federal) @ $240 per 20 round box, you can load a hell of a lot of 450NE!

The Ruger No1 H tropical chambered for 458 Win Mag can be re-bored, and chambered for the 470NE, but only those rifles below a certain serial number. I don't remember what the cut off number is, but it is a way back. It seems the quarter rib screws, and positioning pins are seated to deep in the barrel steel, and the chambering will cut into the bottom of thse holes, or leave the steel too thin under them. The 450NE3 1/4", and the 450#2 NE can both be chambered in the No1H 458 win Mag without hitting them, but the best re-chamber job is to the 458 LOTT, and it can be loaded down to the 450NE 3 1/4" pressures, and velocities without any trouble at all! No extractor work at all, and factory ammo is available, as well. In a pinch, factory 458 Win Mag ammo can be safely fired in the Lott chamber! Once the brass is aquired, the LOTT is cheap to load, and the choice of cheap .458 dia bullets is inexoustable!

I have a brand new, un-fired Ruger No1 H 458 Win Mag on hand, that is scheduled to be rechambered to either 458 LOTT, 450#2 NE,or 450NE 3 1/4", as we speak! I'm leaning toward the 458 LOTT!