I have shot many moose in Alaska and been involved in many more that were killed by co hunters. Moose are pretty easy to kill, just give them 10 seconds or so to understand they just been mortally wounded and tip over. In my experience a whitetail will generally run further once hit than a moose will. They are huge creatures and bullet penetration is needed. A well built 180 grain bullet is a good place to start. and could offer some assurance if you have to take a raking shot. In a perfect world with a clear broadside shot they are easy to kill. We often don't run into those perfect situations when hunting.
In our hunting parties most used either a 338 Win Mag or a 375 H&H (my choice). These thumpers were picked not only because they were a good choice for moose but because we all knew it was a good possibility of running into grizzlies. I killed my last two with a Chapuis double rifle in 9,3x74R. My son shot his last one with a 06 and 180 grain Partition. It worked great.
