I am going to be heading into the brooks range this fall and I am looking at trading in my .220 swift for a good sheep gun. What should I look for? I was thinking .243 or .270 but wasn't sure. Also how concerned should I be about the weight of the gun. I am going to be hiking in from the road and its going to be a trek. So I really want a light gun. I would take my .220 swift but it is heavy. Its a target model so I wouldn't haul it up a mountain.