knowing your rifle and knowing how to dope the wind is the key. Your cartridge of choice is not really as important.
^^^ this is what I have learned to believe . For a while I was planing on getting a 300 win mag or the 7mm mag for long range shooting . I also wanted to get a 40cal pistol an AK , something in 45-70 . the list of cartridges was growing fast and I just stopped that thought proses and decided to stick to a few good common calibers just to keep it simple and cheaper . Thats why I bought the FCP-K in 308 . It's all I need and it will out shoot me for a while . I already have a Ruger American in 308 and if a semi auto 308 comes along at a good price I'll pick one up . I just don't need or want 15 different cals right now . I've got 9mm ,.22 , 223 , 5.56 , 308 , 12ga and I think I'm going to stick with that group of calibers for a while .