Ok If I said I going to build a dedicated 600 yard gun to shoot at CMP, what barrel types calibers would you use? Not worried about optics or weight or specific products. Just off the top of my head I'd say a 20 in. heavy or at least "heavier" barrel. 5.56/.223 wylde over 300bo/6.5 grendel combination? Free float and non compensated. Any opinions? Anything else important I might be missing?

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