AR15 POU: Effective range

[TheBlackMambaXD]

So I have done extensive research as to the P.O.U. of the AR I want to build. My original build was to be a 20" RRA Predator Pursuit upper w/ a Vortex Viper HS-T. According to many responses, using a heavy bullet made by Hornady or such I could make it to 600yds. Thats not to bad in my book, but my question is, with a 20" HBAR upper and a max of 600yds, would I be better off with say an 18" of same model. Even 16" possibly. I don't consider 600yds as "long range" but more high end of mid range. In your opinion would it be better to build a lighter gun more geared for 100-400yds and forget the longish range idea. If I can't achieve say an 800 yd shot with an AR maybe I should just focus on midrange. I do like the RRA Predator Pursuit in HBAR so that will probably not change. They have a 16" and 20" Predator pursuit in HBAR, and the Varminter upper in 16", 18", 20" and 24" Bull barrel. Also I could do a 24" if that would help me get past 600yds or so.
So should I go shorter and lighter, for closer shooting, or longer and heavier with a 24" Bull barrel? Give your ideas. Thanks guys.

 

[C Harrison]

800 yards is achievable with any of the barrel lengths you mentioned albeit somewhat challenging with any wind. You may know, the 77gr SMK can be loaded to magazine length. If you need the bullet to do anything when it gets there other than mark steel or put a hole in paper then a longer barrel will give you very noticeable results at 800 yards. Take an inventory of your predicted shooting distances and determine what the middle 70% of your distances will be. Match the barrel and more importantly twist rate to that middle 70%. Having been in your shoes, once you make the decision you will wonder why you waited so long to "pull the trigger".

 

[TheBlackMambaXD]

Well, I had hoped for a max range of 800yds. I can't say the majority of my shots will be that long, but why buy a car that only goes 55mph. I'd like to be able to eventually reach out to 800. All the RRA Predator Pursuits and Varminters are 1:8. From what I hear that works well for 77gr.