I think it's generally too light for moose but have heard of some youth using the lower recoil round. My feeling is to catch Kings on fly poles you need some skill, as with using light gear for heavy game so especially for youth where the shot placement may not be optimal it'd make sense to use a more voluminous load.I feel black bear shouldn't be a problem with the .243, anyone have strong opinions? I recently picked up the Mossberg ATR in .243 and got it mostly for coyotes, fox, wolves and island deer. Anyone have experience with the ATR?... I haven't got out with it yet.