AR15 Barrel

[RevolvingCylinder]

The problem is this:

I have a RRA STDA2 with the annoying HBAR and post-ban configuration. I want to make this rifle balance better and be able to fire heavier bullets. The extra "evil" features are just icing on the cake(might as well do it right the first time).

What I want to do is make an M16A2-style clone out of it. In the end I want a 1:7 twist 20" Gov't profile barrel with an A2 "flash supressor" and pre-ban front sight base(accepts poking device). Preferably I want a Wylde chamber but will accept 5.56. I also want to avoid paying for extra parts and re-use as many as I can from the operation. I haven't done this before but have researched it and it doesn't look complicated.

Who can supply me with said barrel at the best price?
Does White Oak Armament offer their "Service Rifle Barrel" in 20" and is it a Gov't profile?

 

[Zullo74]

White Oak Armament's service rifle barrel IS 20"

Here's their link......

http://www.whiteoakarmament.com/barrels.htm

 

[Don't Tread On Me]

White Oak's barrel is not GI profile.


I have exactly what you want, I got it from Bravo Company. It is a 20", 4150 steel, NATO chamber, chrome lined, 1/7, government profile (thin under handguards), proof load and MPI tested, M4 ramped, A2 flashhider, with an F-marked FSB that has a bayonet lug. It is as close as possible to a real A2/A4 barrel as you can get. They make runs of these, so you could call them and ask them when the next batch is coming.

It was $400 for this upper when I got it.


Lately, other places are offering such barrels in pretty close configurations. I think Bushmaster makes an occasional run of 1/7 GI profile barrels that has all the features except M4 ramps. Might be a standard offering now. CMMG offers one, although from the picture, it looks ALMOST like a GI profile, taper looks a touch different, but still thinner under the hanguards nevertheless. It is $245.

 

[RevolvingCylinder]

I'm mostly trying to get the rifle to balance right. It doesn't have to taper exactly like a GI barrel, it just has to weigh and balance the same. Why is this barrel so hard to come by? I'm sure I'm not the only one wanting the configuration.

 

[Don't Tread On Me]

Why are they hard to come by? That's a long story that has to do with commercial manufacturers misinforming the consumer base about the benefits of Hbars because they'd like to save money on machining and tooling costs.



Check out that CMMG offering:

"CMMG 20 Gov't Profile Barrel"
http://cmmginc.secure-mall.com/shop/?shop=1&cart=507534&cat=41&

About 3/4 the way down the page.


Here is the Bushmaster offering:

http://www.bushmaster.com/shopping/barrel-assemblies/abbl-20a2.asp

Doesn't say 1/7, but I know they offer it, either by special order, or they offer it in batches from time to time....


Bravo Company:

http://www.bravocompanyusa.com/BCM-M16-Government-20-Upper-Receiver-Group-p/bcm-urg-gov-20.htm

Out of stock though.

 

[RevolvingCylinder]

Thanks, Don't Tread On Me. That's exactly what I was looking for. I'll have to send Bushmaster an E-mail on the availability of the 1:7's and see if they can sell me one any cheaper than CMMG.

 

[Bartholomew Roberts]

Have you tried the heavy rounds out of your 1/9? Some 1/9 barrels have no problem with them and if it works, you can just have your existing barrel reprofiled and threaded and save yourself some money.

 

[soul_rapier]

Here's one place i get my AR parts from http://www.jtdistributing.com/

 

[RevolvingCylinder]

Have you tried the heavy rounds out of your 1/9? Some 1/9 barrels have no problem with them and if it works, you can just have your existing barrel reprofiled and threaded and save yourself some money.

I don't know of anyone who can/will do that for a reasonable price. I wouldn't mind saving the money.

 

[Don't Tread On Me]

Barth, tell me if this is true or fiction.

Some 1/9's do stablize heavier bullets, but they do so at the very edge of stablization. If you have a barrel that works, it may not work at different elevations or different temperatures, particularly cold weather. Wasn't it the military that found that slower twists than 1/7 failed in cold weather with certain bullets?

 

[Don't Tread On Me]

ADCO does reprofiling:


http://www.adcofirearms.com/shopservices.cfm?page=shop

$114 if you want them to do the disassembly/assembly. $64 if you do it yourself. Parkerizing is included in price.


It's also $65 to get the muzzle threaded for acceptance of a flashhider. That doesn't include the flash hider. That would be $5 or $6 for an A2 birdcage, or $20 and up for a phantom or better.


$130 for both if you assemble it yourself. More if they do it. Add shipping and whatnot and the price goes up more....and you still don't get a bayonet lugged FSB.

I'd rather get that 1/7 CMMG barrel and be done with it for $245. You could sell the existing 1/9 barrel to make up some of the money toward the 1/7 barrel.

 

[RevolvingCylinder]

I'd rather get that 1/7 CMMG barrel and be done with it for $245. You could sell the existing 1/9 barrel to make up some of the money toward the 1/7 barrel.

That's what I was thinking. You've got to cover shipping both ways and then there's the wait. I figure I can easily sell my barrel to reduce cost to $200 or less which is what I was aiming for. I will be sending lead through this barrel in the Northeast winters. I load my own rounds and I don't use anything under 62gr to begin with so there's no need for the 1:9 for me.

Thanks again for all the useful info. Hopefully it won't be long until I'm actually using my AR again.

 

[GunnySkox]

Kurt's Kustom Firearms does barrel reprofiling, too:
http://www.kurtskustomfirearms.citymax.com/catalog/item/29585/1132.htm

~GnSx

 

[RevolvingCylinder]

Kurt's Kustom Firearms does barrel reprofiling, too:
http://www.kurtskustomfirearms.citym...29585/1132.htm

~GnSx

Yes but I've calculated it to be not much cheaper than the CMMG barrel.

 

[Bartholomew Roberts]

At that price, I'd probably go with the new barrel too.

Some 1/9's do stablize heavier bullets, but they do so at the very edge of stablization. If you have a barrel that works, it may not work at different elevations or different temperatures, particularly cold weather. Wasn't it the military that found that slower twists than 1/7 failed in cold weather with certain bullets

That is true. My own 1/9 would occasionally produce some decent groups in the summer and but in the winter, 4-5" was the norm at 100yds with 75gr match ammo. If you know you want the heavy ammo and you are going to buy a new barrel, I'd recommend at least a 1/8 twist.

However, if you already have a 1/9 - you shouldn't despair. There is always the chance that it may shoot 75gr and heavier quite well and even if it doesn't give match performance, a 1/9 will stabilize it well enough for self-defense purposes.

 

[Don't Tread On Me]

Thanks for the reply Bartholomew. Very much appreciated to hear 1st hand testimony about 1/9 stabilization of heavies in winter weather.


With groups opening up like that, I'm wondering what performance would be like downrange, like 200, 300 and maybe even 400 yards. The 62 NATO stabilizes in the 1/12 twist barrel at 25 yards, but keyholes at 90 (IIRC from the ammo oracle). Seems to me once the RPM's are lost past the threshold, it goes downhill fast as far as stability.


1/7 for me. Although, I'd use the 75 in a 1/9 for home defense without any worries, either inside or outside, will almost never require shots past 75 yards, probably never past 10 yards really. Internet can exaggerate realistic threat distances....

 

[Bartholomew Roberts]

With groups opening up like that, I'm wondering what performance would be like downrange, like 200, 300 and maybe even 400 yards.

At 200yds, we were shooting on an IDPA silhouette and had rounds all over, including several off the silhouette; but it was 8-10" probably. At 300yds, we ran out of ammo before we could get a decent enough group to measure but still no keyholes spotted.

 

[MisterPX]

With what you want, your best bet is going to be a new barrel. $210 and you're ready to go.