I currently own handguns but I want to get into rifles and start learning how to shoot long range targets. I don't hunt, this rifle would be only for the range. I am trying to do some research but there are so many calibers I don't know where to start. I think I've narrowed it down to .30-06 and a .308. I am on a 400 dollar budget, but I've seen numerous of both calibers on gunbroker for $3-400. Mossburg seems to make both in a pretty affordable rifle. Which is a better caliber as far as power/range/accuracy etc. Any other suggestions? thanks.