I have seen some elk in there that will curl your toes..I mean outright monsters and of course I had a bow in my hands and they were just out of range. At the time I saw them I figured on a 338 being the perfect rifle for something of that size. I would go with the heaviest caliber you can shoot 300 wsm with 180 partitions or 300 win mag or a 7 mag will do the trick but I like the first 2 in that situation. An STW would be nice as well but your not going to find one in a Ruger unless I am really mistaken ..maybe a number 1 you will. Good Luck and let me know how you made out.