Since you metioned sheep I would look for a lite handy rifle.Since this is a all-around gun I would metion several that come to mind.
Remington Mountain Rifle in .280 Rem or 30-06
Browning Micro hunter in 270 wsm or 300 wsm
Kimber Montana m8400 in .270 wsm,300 wsm
There are a slew of good calibers out there.Some of my favaorites are 280 Rem,30-06,7 Rem Mag,270 WSM and the .300 Win Mag or .300 WSM
BBJ