Euro, what about doing a 6.5 grendel? It let's you stay small frame ar, gives you more flexibility at distance. You were planning on a barrel anyway. All you have extra is a bolt, and mags.

223 rounds, even the good ones are kinda BC limited. The slightest wind will screw you. If is gusting, then it's just s guessing game.

6.5 would give you room to grow. Just a thought.