If you're looking for a rifle for something in particular, one of the age-old problems is choosing a cartridge that will perform for your intended purpose. We live in a shooter's heyday right now in that the selection of bullets and rifles is getting close to the peak of what man can possibly do, so there is literally a cartridge and rifle platform that will fit perfectly for what you want to do.
If you want to know the particulars of specific cartridges, this thread on the topic at Sniper's Hide is the place to start. I also highly suggest using JBM Ballistics as a means of calculating the range and power of different cartridges that you may be interested in.
In my youth, the unchallenged answer to getting more range for hunting was to go bigger bigger bigger bigger with a side of as-fast-as-possible. In those days, hunters didn't use rifle scopes with turrets or rangefinding reticles to compensate for distance; duplex reticles were the most popular by far, so in order to get a gain in Point Blank Range, you had to have lots and lots of velocity. This is why there are cartridges like the .220 Swift and .300 Weatherby Magnum. What cracks me up is that even today I know plenty of people who still subscribe to this mindset, and have seriously overbored cartridges for shooting little Virginia deer at ranges that seldom go beyond 80 yards.
To each their own, I guess.
If you're not into being way overgunned, than a little bit of research combined with JBM Ballistics will lead you to the proper hunting/target/tactical cartridge that won't break your shoulder or your wallet. Why feed a barrel burning .338 Thorhammerlighningdragonslayer when you could accomplish the same job with a .270 Winchester?