In my honest opinion the 280 is a great caliber for medium sized game, put a self admitted new to hunting guy behind the trigger and add the pressure of shooting an elk for
the first time it could not end well. I know I will hear some flack on my comment but a light gun in the hands of an experienced hunter/ shooter is a lot different than a newbie.
I have seen my share of guys literally lose their composure when you put an animal in front of them, that being said a lot of great advise comes off of this site and you will be able to filter through the opinions
and come up with what will work for you. My two cents only and good luck and enjoy your time in the bush.