Alaska Magnum,

Good for you, that trip should be the real deal. All those you listed should suffice for brownie (instead of 416 Lot, I'm sure you meant 458 Lott). I haven't hunted brownies yet so the ultimate decision is yours however I have weighed the purchase of a rifle in this range. (If you are weighing ballistics, then I'd recommend you check out Barnes #3 as they do not "sandbag" their loadings for these cartridges.

After a long search and fact finding mission, I settled on a 416 Rigby in a CZ550 Safari Magnum a year ago, its huge case lets you "load it up" to near 416 Weatherby levels or shoot the standard 400gr at 2400fps. The Weatherby is the most powerful of the 416's however, the belt on that fat case limits magazine capacity, perhaps something to consider with DG. My CZ will hold 4 in the mag plus one in the pipe; while the 416 in a Weatherby holds 2 in the magazine and 1 in the pipe. A 416RemMag in a WinM70 would be nice as long as you are satisfied with 400gr. at 2400 (the original 416 Rigby velocity using cordite back in 1911, which the 416RemMag mimics in a more slender case). The nice thing about the 416's is they fly flatter and farther than most 458's and hit with as much or more energy than the 458's which some consider to be more of a "stopper gun."

That said I've been looking at 458's too; thinking of picking up a 458 Lott, Ruger and CZ make one or you can "ream out" a stock 458, BUT only if it was built on a long action --- for example a 458 in M70 would not work.

All these rifles are HEAVY, especially when you load them up, 5 rounds for my Rigby weigh half a pound. Depending on your fitness level you may want to communicate with your guide as to just how hard he is going to "work" you. If it is going to be just absolutely brutal, then something like a 338RUM in a bit lighter rifle may leave you breathing a little more easily.

A great sounding DG hunt, your "steel" should be tempered a little bit "harder" when you get back! A rite of passage.