How old is your brother? How big is your brother? What firearm experience does your brother have? None? Then he should learn to shoot with a .22 LR bolt action for a few months at the very least... then I would consider a .243, .257 Roberts, .260 Rem, 6.5 x 55, 7mm 08, 7 x 57 and stick with bullets less than about 140 grains. A light .308 rifle has a lot of recoil for a beginner. Canadian moose are not hard to kill.
