personally I would want nothing less than a 300mag or maybe 30-06, and would prefer a 338win.mag or 375H&H etc...

I plan to be shooting big slow bullets for moose, in probably the 338 or 375 calibers.

btw aren't moose often in grizzly country? would you want to shoot a grizzly with a 270 or a 375?

what's the minimum required by law?

I forget what it was for my buffalo, I think .27cal/150grs was the minimum.