Help a bolt guy get used to building AR pattern rifles

[tortuga]

So here is my deal; I haven't owned an AR style rifle since the early 90's - I think it was a 6700 series, Colt HBAR with the removable handle. The aftermarket at that time was nowhere near what it is today or I might still have it . Since then I have mainly dinked around with single shots and bolt guns - Remington and Savage mostly - for varmint hunting. Priority was the ability to put the first shot on the POA, then the next shot, then the next shot, at the highest velocity that worked for .17, .223. 22-250 and .243. Reload a lot.

I am now working on building a new AR and tweaking one I have. Done a lot of research. What surprises me is that much of what I did to work on a bolt rifle doesn't get a mention in the AR world. Things like bedding an action - who cares about lower to upper fit? bedding a barrel? who cares? headspacing? It's all milspec. Turning necks? forget about that one and throw out the idea of neck sizing as well.

The one that really throws me is that nobody seems to be interested in truing up the receiver and barrel. That is remington 700 tuning 101.

I'm not saying it's wrong, just different.

So for someone that wants to tweak every bit of accuracy out of the system, what do you do beyond just buying quality components?

FWIW my rig right now is stag upper/lower, JP BCG, trigger & float tube, Dennys' Operator barrel, ACE stock.

[ShooterSteve]

I think that even though stuff is mil-spec, there is a ton of quality going into a lot of parts that are being made. Also when you look at the repeat ability of manufacturing with upgraded processes like cad, and the computer side of machining, more people can turn out quality parts. There is a lot less "magic" around building a rifle. Two weeks ago I was at the range, mostly to let my friends shoot, so I just did a little dot shoot to practice a little. I was shooting at 3/8" dots with my AR, and had a 50 percent hit rate. My friend was astounded. All I had was a little "home built" AR. He didn't really know that every part on that rifle was top shelf, but if you build it with good parts, most likely it's gonna shoot!

[californiasushi]

This is the best article I've seen on what you're asking. YMMV.

http://bulletin.accurateshooter.com/2011/10/what-makes-an-ar-accurate-whitley-offers-answers/

[tortuga]

This is the best article I've seen on what you're asking. YMMV.

http://bulletin.accurateshooter.com/2011/10/what-makes-an-ar-accurate-whitley-offers-answers/

Great article, thanks for the link. They recommend checking headspace(bolt play, in the article), truing the receiver, tightening up the upper/lower fit, watching what you do with the crown, etc.. Very similar to a bolt action build.

[dauntedfuture]

No one in the high power world that I knows messes with the truing up the upper receivers. Upper to lower fit does not make it shoot better but it does help keep the sights from moving around when your in position. A confidential source did tell me that if they ever have a gun that does not shoot well they try the barrel on another upper and it sometimes "fixes" the problem.

[MarkCO]

If you want a better barrel extension to receiver fit, ditch the Stag upper and buy a stripped JP upper. While shims and glues and epoxies have been used, the tighter fit is a big part. Then you just have to install the barrel nut correctly. Get a copy of the Noveske barrel nut installation instructions, follow those with the JP receiver and you will be happy, happy, happy.

[zhunter]

If you want a better barrel extension to receiver fit, ditch the Stag upper and buy a stripped JP upper. While shims and glues and epoxies have been used, the tighter fit is a big part. Then you just have to install the barrel nut correctly. Get a copy of the Noveske barrel nut installation instructions, follow those with the JP receiver and you will be happy, happy, happy.

I built my first ever AR last year, I did everything but marry the barrel to the Upper, MarkCO did that part for me with his stuff from Carbon Arms. Put a high quality BCG and a good trigger on it and you're ready to go. 1st build netted 3/4 MOA for me.

[LCDRJGB]

I think most of the bolt gun stuff done to enhance accuracy really just polishes the cannonball. If you get a properly chambered Rem 700 5R and drop it into a bedding block chassis system, put in a descent trigger (e.g., tuned remmy or timney), use match or high quality hand loads, and have descent optics then you can shoot "almost" as well as with all of the accuracy enhancements. Case and point with my wife's 5R (her shooting) at 100 yards:

Most important are (1) good barrel, (2) barrel free floated, (3) good ammo, (4) good trigger, (5) good sights/optics, and (6) compensator if a heavy recoil round. You get a little bit extra with stress free bedding, cutting a "match chamber", and truing but at that point I think your scraping the gravy off the sides of the pan. Using quality parts on your AR build should get you all of the attributes above.