I'm putting together a rifle for a buddy for this discipline. I've got the rules for the class he will be shooting, but I need to find a 20'' match grade barrel with the front site post already attached if I can. I've found a couple of options through whiteoak, but cant find anything with the front site already attached. Barrel can be any larger outer diameter than .750''. Does anyone have any suggestions for a good barrel that fits the bill for what I'm looking to put together? Any help would be greatly appreciated. Thanks in advance.

You might give RRA a call.  Their NM uppers are pretty good, and they may sell you a barrel with the front sight installed.   Or, you could go with a complete upper.

http://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=268

Their drop down menus for purchasing I believe include the option of adding that feature to your purchase.  I will check their website later.

The White Oak service rifle barrels have milled flats for their windage adjustable FSB.  The FSB simply attaches with set screws.  You can order the barrel, FSB and the gas tube all from White Oak.

Yeah, WOA's front sight towers use opposing set screws so the owner can place his rear irons dead center and establish a perfect mechanical zero by adjusting the tilt on the front sight post. This is a huge advantage when shooting iron sights at 600 yards on a windy day.

Most AR15's have the rear sight shoved to one side or the other to get a zero, this can interfere with your ability to get on target at long range. If you intend to shoot a flat top with a 4.5x or lower magnification optic and don't care about a perfect mechanical zero on your irons than a standard pinned front sight will work just fine.

I used a RRA NM gun for several years and it shot lights out. The barrel was super accurate with 75 GT blackhills match. I put a 6-20 scope on the A2 carry handle to get a base for accuracy and was constantly getting .75-.80 groups. So I'd reach out to RRA for a barrel.

Almost all NM A2 uppers have a free foat tube under the handguards. White Oak, RRA, etc. The White Oak set screw FSB is easiest to install and aligned after getting it all put together.

If you contact white oak they'll probably do it for you. I emailed them asking if they could bead blast a barrel for me and I got a response in a about an hour saying yes.

Thanks for all the input, fellas. I'm going to reach out to White Oak today and see what the options are.

RRA is also a solid option so I'm going to give them a shout as well. Just need to see what the best bang for the buck is.

CLE