16" 1-7" AR-15 barrel

[ocabj]

Anyone know where I can get a 1-7" barrel in a 16" length for an AR-15 (with flash suppressor)? The Bushmaster and RRA sites only show a 1-9" for a 16". I'd prefer a Colt heavy barrel if possible, since that's what I'd be replacing.

 

[Bartholomew Roberts]

http://www.sawlesales.com/ sells Colt products; but they ask a premium.

I believe http://www.cmmginc.com/ also offers 16" 1-7 barrels.

 

[rock jock]

Bushmaster did a limited run earlier this year. You might call them them to see if they have any left over as they are not advertised on their website. They were only sold as HBARs. I had to send mine off to have it turned down to a M4 profile.

 

[Duke of Lawnchair]

Bartholomew Roberts hit the nail on the head.

Check with Sawsales and CMMG.

You can also look up folks such as Grant @ G&R Tactical, Wes @ MSTN, Jason @ JTAC Supply just to name a few. These fellows and their outfits carry the LMT 16" 1-7" 16" LMT barrels (M4 profiled).

AR15.com's equipment exchange forums are also a great place to look. I thought I saw a member or two selling 16" 1-7" HBARs not too long ago.

-Jim

 

[ocabj]

Thanks for the references. I'm not in a real rush to get one, but my 16" barrel is over 10 years and several thousand rounds old, so I'm going to get a new barrel eventually.

Why is 1-9" easier to find than 1-7"?

 

[mrapathy2000]

just curious whats the advantage of 1-7 over 1-9?

see the russian AK's use 1-7.

 

[Bartholomew Roberts]

Well, there used to be no advantage to 1-7 unless you wanted to fire VLD rounds for long range match or needed to fire 62gr tracer.

Then they discovered that the heavier open-tip match rounds were very effective in an anti-personnel role and the 1-7 barrel got a lot more popular. With a 1-7 barrel, you know you will be able to use the heavier 75gr and 77gr match rounds to their full potential. With the 1-9 barrel, you might get lucky but chances are good that you will get less than stellar accuracy (4-5MOA) with the heavier rounds.

 

[g56]

1/9 twist is the standard twist in the AR-15, it is considered the all around twist.

From the Ammo Oracle:

Q. What twist rate do I want for my rifle?

Probably 1:9, but it depends on what kind of bullets you intend to shoot.

Special purpose rifles often have uncommon twist rates. For example, if you are building a varmint rifle and want to shoot the short 35 grain, 40 grain, and 50 grain bullets, a 1:12, or even 1:14 twist would be best. On the other hand, long range High Power shooters often select 1:8, 1:7.7, 1:7, or 1:6.5-twist barrels to stabilize the long 77, 80 and even 90 grain bullets used for 1,000 yard competition. Additionally, new testing of heavier rounds (68-77 grains) seems to show that they perform very well in simulated tissue and may be a better defensive choice than 55 grain or 62 grain rounds. The majority of shooters, though, typically shoot bullets of 50 to 69 grains in weight (note that the 62gr SS-109/M855 bullet is as long as a 71 grain lead core bullet) and should select 1:9 twist barrels. At typical .223 velocities, a 1:9 twist will stabilize bullet lengths equivalent to lead-core bullets of 40 to 73 grains in weight.

1:12 twist rifles cannot stabilize SS-109/M855 bullets and 1:7 twist rifles are slightly less accurate with lighter bullets and will often blow apart the thin jackets of lightweight varmint bullets. The 1:7 twist is used by the military to stabilize the super-long L-110/M856 tracer bullet out to 800 yards, but unless your plans include shooting a significant amount of M856, the 1:9 twist rate is better suited for general use.

There is, of course, an exception: if you want to use loads utilizing the heavier, 75-77 grain match bullets currently used by Spec-Ops troops and other selected shooters, you'll want a 1:7 twist barrel. Although military loadings using these bullets are expensive and hard to get, some persistent folks have managed to obtain a supply, and will need the proper barrel twist to use them. Anyone who foresees a need to shoot this ammo should consider a 1:7 twist barrel.