For deer, you can pick just about any centerfire cartridge and it will kill it. Most practical for a non handloader is the common stuff like .308, .270, 30-06, and even the lowly .243 with good bullets is a good deer killer.
Come on now, the 243 isn't that lowly!
About 2200 foot pounds of energy with a 100 grain bullet, compared to about 1825 for the 30-30, or at the speed most 130 grain bullets are driven in an average 270, maybe a touch over 2400.