I guess I'm "Old School", so i only use bolt action rifles. I use a .243 with 87 vmaxes, a .223 AI with a 55 vmax and a 6AI with a 87 vmax. I got 2 .308's this year and am shooting a 110 vmax just for fun. They really blow up 2 liter plastic bottles at 200 yards!
If i want to save a pelt I like the .223 AI. If you dont hit bone, little bitty hole in, no hole out!