i have a few different rifles, but the two calibers i wouldnt part with would have to be my .223 Rem and .308 Win,
you can get ammo pretty much anywhere, and as long as they are standard NATO calibars, ammo commercial ammo will be pretty cheap, and should anything nasty happen, you know you can always get ammo, if you have to.....
I have shot a lot of stuff with them, i cant say that the same animals were "30 % deader" with anything bigger, although i would say that sometimes there are shots i either pass up, or have to really concentrate on to have them come off ok, but is that a bad thing?
Im pretty sure anyone in the 1750s would have given thier eye teeth to have a five shot bolt action witha scope!
What are your ideas about you fav calibers????