Re: Long range AR
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">My M4 with Aimpoint is fully capable of engaging man sized targets at 300 from standing supported.
If you are looking for a "precision" AR, then you want a 1:8 or 1:7 barrel 18-20" long. Free floated handguards, and a good optic. Anything else just supports the barrel. A light two stage trigger is a plus as well as a good stock.
You will want to set the rifle up to shoot 75-77gr projectiles. You can go 80gr if you want to single load them through the ejection port, but 77gr is the longest you can mag-load.
Depending on who you source the barrel from you are going to have a rifle accurate out to a lot more than 300 yards. </div></div>
+1
I would stick with a minimum of an 18" barrel to keep velocities of the 75gr and heavier projectiles up as high a possible. It is amazing what 2" of barrel can cost you in terms of terminal ballistics and accuracy at extended ranges. Depending on whether you plan to be humping the rifle around and how much your final product will weigh with optics, etc., you might even think about the 20" barrel although it is not absolutely necessary.
Lilja, Krieger, Douglas, Lothar Walther, and many other manufacturers make excellent match barrels.
Flat-top/A3/A4 upper for ease of scope mounting. Also, plan to spend at least the cost of your rifle on quality optics and mounts/rings. The best rifle in the world is little more than a club without proper optics/mounts and a shooter who knows what they are doing.
You'll want a free-floated barrel for obvious reasons (there are too many mfgs to mention on this front...look around ARFCOM and here for pics). Personally, I like Daniel Defense, Larue, PRI, and Badger. YHM also makes some quality, lower cost alternatives for FF tubes if the DD and Larue stuff is too much for your wallet.
There are some great selections for triggers. Giesselle (sp?..sorry..can't spell). I have one in my POF 308 and it is excellent. I also like the Timney drop-in units.
The big question you'll need to ask yourself is are you going to put together a parts gun or are you going to have a good AR builder set up up with exactly what you want.