I have a Professional Ordinance Carbon 15, but it is not giving me the accuracy that I feel it should.
So I am planning a first time build of another.
Been reading alot here and planning and pricing out components.
I am looking at a rifle capable of shooting 1" groups at 100 yards.
I assume the majority of that accuracy will come from the barrel.
At this point, I'm looking at a mid length system with a 16, 18, or 20" barrel?
Guess I am asking if I need to be looking at a long heavy barrel to expect that type of performance.
I see the cost varies greatly for barrels as well.  Is it logical to expect a $150 barrel to shoot those groups?
Is the bolt critical?  I have found them for $120 and up.
Found what I want at Palmetto as far as lower receiver and lower build kit w/ MOE stock.
Looks like I can build the upper or I can buy one for about the same cost.
Just wanting to know what direction to start with.  
Am ready to order, but have not bought anything as yet.
Just looking for some real experience ideas.
Thanks for all the great information so far.
Shane

White oak barrel

I've read that after 20"s you don't get much more out of it that didn't stop me from going with a 24" flutted and ported barrel from J&T. I haven't finished the build yet though so can't say much about it yet.

But you'll also want a trigger along the lines of CMC or Timney. A mount like a Larue LMT 104(?) and a QUALITY optic.

As for a bolt? I don't know, I got a Spikes...

But your barrel, scope, mount and trigger will be most important.

FWIW, my 6721 did 1 moa (at 100 yards) with fed gold medal when it was off the shelf for a 5 round group.

16 to 20 barrel.  After 16 look at rifle length gas system.
A good trigger, a soild scope and mount, and a quailty barrel.
Rest of the parts are kind of like icing on a cake.

1 moa at 100 yards is not asking that much from a quailty built AR using Match grade ammo.

Thanks, was thinking an 18" or 20" barrel, still wondering if a heavy barrel would be necessary to expect that type of accuracy.  Maybe it would just allow more shooting before the barrel heats up?

A quality barrel that's been free floated and a good trigger.

The profile of the barrel isn't that important, but a heavier barrel will be easier for you to hold steady and will heat up a little slower.  On the downside, it will also retain heat longer.

Free floating it will remove outside influences from affecting barrel harmonics, allowing greater consistency.

The trigger has no affect on mechanical accuracy, but it makes it easier for the shooter to turn mechanical accuracy into practical accuracy.

I have a 20" RRA varmint gun. It has been a sub moa with any kind of decent ammo. It shoots M193 at 1.5" 10 round groups. My best with hand loads is under a half inch five round groups.

A good gun is needed but it has more to do with the shooter. A good barrel, trigger, ammo, and fit to the shooter is nessisary. But after that it is up to the shooter. It has taken me a while to train up to shooting sub MOA. The best gun you can buy won't do much without a good shooter.

i have not used this company befor..!  but i ran into their website a while back, and i was really impressed what they had to say about some of there barrels...
this is a link to one of there barrels... copy and past the link becuase  i dont know how to add links on ar15.com  
i was thinking of trying one of these barrels out they say that they give a 1 MOA guaranty,  and hell they ara listed at 160 buck that is a good price for the supposed guaranty of 1 moa.. i think...

here is the link:
http://jsgunparts.com/store/index.php?main_page=product_info&cPath=16_46&products_id=626

i cant vouch for them but hope this helps...

Funny I stumbled on this post.
I JUST finished my varmint/hog gun.

Specs:

Stag Stripped Lower
Stag A3 Upper
Stag 24" 1:8 SS Bull Barrel
Stag BCG
Geiselle SSAE Trigger (THE FREACKING BOMB BTW)
Magpul PRS Stock
Model 1 vented Rifle length FF hand guard
Harris BiPod
Model 1 Scope mount
Leupold Mark AR 6-18x40 MilDot scope.

Not really sure how much I have in it, I don't really care. Not as much as you or the wife thinks.

Just papered it today. First 15 rounds, 3 shot groups, BIGGEST group was a single MOA.

Dialed it in with Blackhills 223 REM 75 gr HPBT ReManufactured ammo.

This bitch can shoot!!!!!!!!!!

I look forward to dialing in a home made 75 gr or 77 gr. boat tail and getting it down to a VERY fun .25 MOA.

Good information, thanks guys.  Tonight I ordered the parts for the lower.  I guess my custom build is past the idea stage now.  The J& S barrels do look good on paper anyway.  Adding up the costs, it seems to be cheaper to buy a complete upper.  Don't have to decide that yet.

Don't forget to include shipping

Every DPMS stainless barrel w/FF handguard  I have used far easily exceeded your requirements even with a standard trigger.

This is looking like the best deal that I've found price wise.

http://www.palmettostatearmory.com/2096.php

Not sure about the chamber.  Don't know anything about it.
"Please note the 223 Wylde chamber is designed to function with both the 5.56 NATO pressure rounds and SAAMI spec 223 Remington rounds."

Any downside to the Wylde chamber?  I would be shooting both reloads and some factory ammo.
I would opt for the :
- Add a Midwest Industries T9 Free Float Rail and Upper Height gas block for $100 -

Do you guys think this combo should meed my MOA requirement with it's 16" barrel?  Quality of the barrel?  1:8 twist should shoot heavy and lighter bullets I'm thinking?  Thoughts?

Including shipping the upper is $544.95 and I havne't found where I can buy components and assemble an uper for that $.
The MOE Lower build kit is ordered and planning on getting Palmetto lower ordered tomorrow.
Complete rifle would be $743.45 plus sights/scope.

I do understand that the scope, trigger, and shooter play a large part in the rifle accuracy.  
I just want to start with components that are capable of shooting close to an inch at 100 yards.
The Pametto upper ends up about $160 less (depending on the barrel) than if I bought all the individual components and assembled it myself.
Seems to have all the features I am looking for.  Of course I'm still learning and ideas can change.
Just wondering what you guys think.
Thanks,
Shane

The 223 Wylde is the answer to the 5.56 nato higher chamber pressures. 223 REM and 5.56 nato are for all arguments the same, EXCEPT...

The 5.56 Nato is a military round and has higher muzzle velocities and higher chamber pressure. The physical differences are in the throat of the chamber.

223 Rem has a shorter throat, I think (others will correct me if I am wrong) and the commercial 223 loads lower velocities and thus lower pressure. The WYLDE chamber addresses this with a VERY happy medium of the two similar but at sometimes different cartridges.

The other option is to make sure you have a 5.56 nato chamber. that can MORE than handle the 223 rem. The wylde will do this too.

I would say that this rig should meet your expectations nicely. All you need is a decent trigger and scope.

Thanks, it has everything that I think I wanted.
At least today, that can still change.
Maybe an 18" barrel would be the only other thing, but that was just an idea for alittle better accuracy.  Not sure what real perfomance I'd gain.