If you want a custom .270 Weatherby on a 700 action, then go for it. Nothing wrong with that. After all, it's your money and your choice. If it were me, though, I'd choose a different action (maybe a Win. 70 or Sako 75) and probably the .270 WSM instead of the Weatherby. I shoot a .300 Weatherby Sako and it's an okay round, but there's nothing magic about Weatherby cartridges, nothing at all.