ORIGINAL: Soilarch
He considers the 30-06's drop at 200 bad...and wants something to shoot out to 400. Given those requirements what's NOT going to burn barrels? I agree with your 300 WM suggestion, but to rule out the weatherbys....this is precisely the kind of stuff they are made for!!!!!!!!!! I'd throw the 7RUM in there too.
Will they burn barrels? Yep
Will the cost alot to shoot? Yep
Will some of them kick like a rabid mule on PCP? Yep
Do they fit the requirements of original post? Yep
Here's the thing, at 400yards the WIN mag is only 5" flatter than the good ole 30-06. The standard by which he is saying is "real bad" and they are both already sitting around 20" of compensation at that range so we're only talking about 1/4 improvement!!!!! The 7RUM is closer to 8" as well as the 300 RUM and 300 Weatherby. This is with a 230 yard zero which is just about optimal for 6" target and all the 30 cal throwing 180 grain bullets. That 30-378 is another 200 fps ahead of the game so it may be just the expensive-to-shoot barrel-burning gun he wants.
To answer the original quesion: Take your pick of the suggested cartridges and realize you cant have your cake and eat it too. My personal suggestion would be to take the your money, buy a laser rangefinder a ton of ammo for that 30-06 and put a lot of time in the at the range...but that's just me.
Peace out, it's entirely toooooooo late.
It's never too late, by big bore I'm thinking he wants to take anything in NA including big bear, plain and simple. Which makes the case for .30 caliber or 180 grain and above, which I consider the "bear" minimum. A .300 Win Mag or a .300WSM will satisfy that want, no bigger, no less. If you get the .300 Win Mag you can alwaysopt to buy the Weatherby cartrige to out perform the.300WSM but you will pay a hefty price. Otherwise, the .300WSM slightly out performs its predecessor and costs generally about $2 more for a box of 20.
My nextrifle for my collection will be a .300 WSM, probably in a Weatherby Vanguard Stainless Synthetic topped off with a Nikon Monarch.
Peace out yo's.