Doing an AR-15 build. Need a recomendation for a match class barrel

[Rob]

I am building an AR-15 upper.  99% sure I want to do it in 6.5 Grendel.

Regardless, I need to select a barrel.  Some thoughts on what I am thinking:
-I am trying to build a gun that will be sub MOA to 300+ yards
-I am looking for a longer barrel in the 24 to 26 inch long range (but this is not required)
-I want to build the upper so I don't want a completed upper.
-head spacing makes me nervous.  Would like to buy a bolt and barrel that are already headspaced.
-Options like fluting are a plus!

What have other people picked up and been happy with?

[Biggerhammer]

I've shot the Grendel a bunch on the AR platform. If you don't know already. The 6.5 Grendel, 6.5 LBC, .264 LBC are all one in the same. I have shot AR's with barrels stamped in all three. All the ammo and brass is interchangeable. I shoot allot of 6.5 Grendel Lapua brass through my .264 LBC and a bunch of .264 LBC through my 6.5 Grendel barrels.

Alexander Arms has been a wreck, rumors run amuck as to why. Getting a barrel from them is near impossible, giving them your money is easy. 8 months plus wait for a barrel, no thanks.

Allot of barrels have been made in limited runs chamber in 6.5 Grendel, nothing consistent for one reason or another. My brother and I just haunt shooting forums and picked our barrels up used.

If you can find one Sabre Defense does a excellent 6.5-Grendel barrel but your best bet for a quality barrel chambered in 264 LBC and in a reasonable amount of time is BlackHole Weaponry. My 6x45 barrel from them is insanely accurate!

http://www.blackholeweaponry.com/catalog/index.php?cPath=23&osCsid=67cce0bb38026bda6e907c07e9eb2e93

One of my younger brothers piloting a 6.5 Grendel during this years deer season. The carbine was built by him with a Alexander 16" M4 carbine barrel. The carbine pictured has taken Mulies clean out to 493 yards.

[JohnVH]

the FPS difference from a 16" to a 26" barrel isnt that much, buy a quality barrel in the length you think will be easy to pack and use.   That said, I went with a 16" Grendel, it shoots sub moa groups, throws a handloaded 120gr nosler at just under 2500fps.

300yds isnt that far for a grendel, they target shoot them to 1000yds ++

From above

Alexander 16" M4 carbine barrel. The carbine pictured has taken Mulies clean out to 493 yards.

[Biggerhammer]

When we first got several Grendel's put together, I purchased a couple hundred Lapua AA brass and my brother picked of a case of the custom loaded stuff pictured bellow. WICKED ACCURATE! through everything we have run it through, including Mulies.

This is a pic of one of the boxes of ammo we shoot(50 count). The brass is headstamped. .264 LBC, runs beautiful through AA chambers and barrels but for factory stuff the Hornady factory 123 A-Max is the ticket, accurate and great on Yotes and chucks at around 20.00 for 20 loaded rounds. It is worth buying just to get the brass after you shoot it. The AA Grendel Lapua brass is a buck a piece by itself, if you can find it.

[Rob]

Good info, thanks!  I had not heard about the .264LBC/6.5 Grendel being the same catrtridge.

So a stupid newbie question...

how difficult is it to do the headspacing?  It makes me nervous to try that on my own.

[Rob]

also, what is the difference/benefit of a .750 vs. a .936 gas block?

[Biggerhammer]

also, what is the difference/benefit of a .750 vs. a .936 gas block?

No heads spacing is needed. Slap the barrel on, install the Grendel bolt in your bolt carrier. Swap the 5.56 mag for the Grendel mag and your good to go. Don't use a 7.62x39 AR bolt for a 264 LBC or 6.5 Grendel barrel unless the barrel is noted as being heads aced for the 7.62x39 bolt.

The only difference between the .750 & .936 has block is the diameter. .750 fits most of your standard barrels and the .936 gas block fits your heavier match or varmint contour barrels. Most barrels you can read the gas block specs on the before you purchase all of our's run .750 gas blocks.

When it comes to head spacing on let's say a 5.56 AR. The barrel locks into place and the bolt into the carrier, the only way to be not properly head spaced is to have a out of spec barrel or bolt either in which would have to be replaced or you have a seriously worn bolt which can simply be replaced.

I have built ALLOT of AR's and with good bolts and all barrels I have used in different Chamberings. I have NEVER had a head space issue.

[FALFire]

also, what is the difference/benefit of a .750 vs. a .936 gas block?

The only difference is barrel contour, large heavy bull barrels will have the .936" block where as the standard heavy barrel will have the smaller more common .750" gas block. It's all about barrel diameter.

Your best bet is to purchase the barrel and bolt as a matched set, most suppliers will have that option available. Since you need both this is the best way to get set up, otherwise, if you already had the bolt in most cases you can use it with a new barrel. But still I feel the matching set is the way to go, the headspace will be set from the barrel manufacture, you will simply slip the barrel in place and screw on your choice of hand guard.

[Biggerhammer]

also, what is the difference/benefit of a .750 vs. a .936 gas block?

The only difference is barrel contour, large heavy bull barrels will have the .936" block where as the standard heavy barrel will have the smaller more common .750" gas block. It's all about barrel diameter.

Your best bet is to purchase the barrel and bolt as a matched set, most suppliers will have that option available. Since you need both this is the best way to get set up, otherwise, if you already had the bolt in most cases you can use it with a new barrel. But still I feel the matching set is the way to go, the headspace will be set from the barrel manufacture, you will simply slip the barrel in place and screw on your choice of hand guard.

FAL is spot on with the bolt/barrel package, all barrels in .264 LBC & 6.5 Grendel I have purchased came with the matching bolt.

[FALFire]

Not to hijack this thread but.......Hammer.... Your 6x45 barrel, what is your favorite load? I have a BHW 6X45 10 twist 5 groove that will shoot only 58 V-Max boolets with reasonable accuracy, everything else is a total turd for groups.

[mountainman]

recently put 2 more AR's together with Blackhole barrels. Will never use any other barrels. One a .223, one a 6X6.8. Yes, very accurate ant with their polygonal rifling, easy to clean and no leading when properly broken in.

[dontgetcrabs]

I also recommend bhw barrels great quality reasonably priced. Waiting for my latest one to arrive an 18" 6x45.

[Jim the Plumber]

Not to hijack this thread but.......Jim the Plumber, Your 6x45 barrel, what is your favorite load? I have a BHW 6X45 10 twist 5 groove that will shoot only 58 V-Max boolets with reasonable accuracy, everything else is a total turd for groups.

Try the 85 grain Sierra spbt over 23.5 Ramshot Exterminator and LC primed brass.  I'm getting sub MOA with a 6X45, no name 10 twist 18" rifle length gas port, barrel.

[Jburke]

So I have to ask because you guys have me thinking crazy now.  I currently have an AR in 5.56.  I can change out the upper to a 6.5 and buy new mags and basically have a new gun, correct?

[Biggerhammer]

So I have to ask because you guys have me thinking crazy now.  I currently have an AR in 5.56.  I can change out the upper to a 6.5 and buy new mags and basically have a new gun, correct?

You don't even have to change out the upper on your 5.56. You can purchase a 6.5 LBC/Grendel barrel, bolt & magazine. Switch the bolt out in a flash, jam a Grendel Mag in it and swap the 5.56 barrel for the 6.5 LBC/Grendel barrel and off you go. Change it back to 5.56 anytime you want. You can also build or purchase a complete 6.5 upper and magazine. Pull your two take down pins, remove your 5.56 upper. Drop your 6.5 upper on and gas it up with a Grendel mag and your good to go.