If you like Weatherby rifles and plan on taking 300-400 yard shots on elk you might want to consider the Weatherby Vanguard. It is made for Weatherby by Howa but the build quality is equal to other Weatherbys and its accuracy is probably superior. I have a Weatherby Vanguard in .300 WBY Magnum that shoots 1/4 MOA groups with factory ammunition. With the synthetic stock it is not too heavy and can be had brand new for as little as $500. The .300 WBY Magnum would be perfect for elk at 400 yards, the one caveat is the recoil is likely to be somewhat more punishing than you are used to if you have only been using the .280 for a long time.