Want a round for 500-600 yards for deer/antelope/yotes. Thinking .22-250 AI, .22-6mm or the good ol .243. With the new 65gr from Sierra, should be good for deer/antelope. Has anyone tried the 75gr A Max on larger animals? I have a .25-06, but would like another rifle for a back-up. I have dies and bullets for the .243, but I would like to try some fast twist bullets out of a .22 centerfire. If I don't go with the .243, it will give me a reason to buy one down the road, since I have the components!!!! What do you guys think?