I think we should first distinguish that battle and assault rifles are two different classes of power. All things being equal between the AR10 and AR15, you will need to decide on what you necessarily want the rifle for. You can fire .223 all day with reckless abandon, but the .308 is expensive. If you are currently reloading for the cartridge, though, I would probably choose the AR10. Really, it's totally personal preference. I hear the AR10 is one of the most supreme semi automatic .308s ever manufactured and for that reason alone I am interested in one (I currently own a "re-tooled" MAS 49/56 and only wish I had an M1A). You also have an option in a Mini 14 for .223. Don't buy the hype. They're decent rifles.
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