Your point about a .45/70 is well taken. This discussion started on another thread and I never really explained the situation over here.
The deal is that most of the time I'm not hunting or backpacking when I run into bears I'm just out fishing for the day. Here on Kodiak theres roughly one bear per square mile - they're everywhere!
But you don't want to drag around a heavy rifle or shotgun just to catch a few fish. I normally have enough crap to drag around without making life even more difficult.
My thought was that a Trapper would be handy and accurate enough to make a head shot on a bear and yet be light enough to carry around with a lot of other gear. No caliber is a guaranteed stopper when a 1500 browny is coming at you - it has to be a head shot and a little carbine may serve better than a heavy rifle in that situation.
The Bears and Bear Maulings Page: members.xoom.com/keithrogan