I suppose this will be a rambling internet answer because:
I have rifles chambered in 375 Ruger, 375 H&H, 338 Win Mag; no 416 Ruger, though a 416 Rem Mag. I consider the 338 Win Mag a definite all-arounder for larger game. If I got down to only one rifle, it would be chambered in 338 Win Mag.
I do really like .375's, and the past few years having been toting a 375 Ruger. For me, the difference between the Ruger and the H&H is strictly the rifle platforms, nothing to do with the belt or the purported/actual velocity differences. I do like the Ruger case design. But, hell I like the sloping classic H&H design also.
My logical side (Not my purchasing side) says; Bob's comment above is correct, regarding the 416. Though, I have never wished that I had a smaller caliber when carrying a 416 or larger. But, this has very much to do with the terrain that I hunt and travel in.

Originally Posted by wildchild2010
A rifle for hunting Alaska Black Bear, Bou, Moose and of lucky to draw a Brown Bear tag one day? .375 Ruger, .375 H&H, .338 Win Mag, .416 Ruger Big Game. They have all been proven in the field and have done well and ammo is not very hard to come by on any of them.

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