Help with new barrel

[olp73]

Help me chose my new barrel! I want the absolute best based on the following criteria:

Midlength or longer gas system

16" long

Lightweight .625'ish under the hand guard

.750 at the gas block

Threaded for compensator.

Chrome lined

…………….and as accurate as possible. It would also be nice if it lasted a little see my former post : )

http://www.brianenos.com/forums/index.php?showtopic=156094

Edited July 25, 2012 by olp73

[gng4life]

The JP barrels are pretty awesome! Here is a link for one that is very close to what your specs are:

http://www.jprifles.com/buy.php?item=JPSM223-16L8K

[landshark45]

If its gotta be chrome lined iv had great results with several Daniel Defense builds.

DD has a few barrels that meet your criteria specs.

It's been my experience even with el cheapo steel cased ammo they hold 2moa.

Won't break the bank either. I recommend getting one with the gas block already installed.

[olp73]

The JP barrels are pretty awesome! Here is a link for one that is very close to what your specs are:

http://www.jprifles....m=JPSM223-16L8K

I think I am gonna try a chrome line one this time, but thanks. : )

[olp73]

If its gotta be chrome lined iv had great results with several Daniel Defense builds.

DD has a few barrels that meet your criteria specs.

It's been my experience even with el cheapo steel cased ammo they hold 2moa.

Won't break the bank either. I recommend getting one with the gas block already installed.

Thanks, but how are 1:7 barrels with lighter bullets? (55gr) and why do you recommend one with preinstalled gas block?

Edited July 25, 2012 by olp73

[Sleepswithdogs]

If you haven't already, you might want to do some reading over at AR15.com Most here shoot 3 gun and so use SS 18" barrels. Over at AR15.com almost everyone there shoots a chrome lined barrel, many shoot 14.5"-16" barrels. Not that people here don't know, but the type of barrel you are thinking of is much more common over there.

You might also check Brownells, they seem to have a lot of good deals on barrels and all kinds of ar stuff.

Military typically shoot 1:7 with 55g. Though there is some controversy how the 1:7 became the standard twist for the M16. There are people who say it was a bureaucratic decision in Belgium that influenced the adoption of that twist for the M16, and that a 1:9 is actually a better twist rate for this rifle.

Tar

Edited July 25, 2012 by Sleepswithdogs

[carbon9]

Look into Criterion Barrels if you want chrome lined or see if you can find a Nitrided/Melonited barrel as you are looking for longevity. I believe Loki(vendors tent section of BEnos) offers one. Best of luck.

Is reloading ammo an option for you, if so, that may be your best bet long term?

[RWF]

white oak,and there are more into NRA high power style shooting. and i think they great! i use there barrels for 3 gun and F class shooting at 600 and 1000, and this with a 5,56 factory loaded round. they are always out of stock and if you think that is what you want called them what you want, pre-pay so you will get one. if you do not pre pay you have to wait till prepaid orders all filled and if one is left and you are fast you can get one.

[Alaskapopo]

If you haven't already, you might want to do some reading over at AR15.com Most here shoot 3 gun and so use SS 18" barrels. Over at AR15.com almost everyone there shoots a chrome lined barrel, many shoot 14.5"-16" barrels. Not that people here don't know, but the type of barrel you are thinking of is much more common over there.

You might also check Brownells, they seem to have a lot of good deals on barrels and all kinds of ar stuff.

Military typically shoot 1:7 with 55g. Though there is some controversy how the 1:7 became the standard twist for the M16. There are people who say it was a bureaucratic decision in Belgium that influenced the adoption of that twist for the M16, and that a 1:9 is actually a better twist rate for this rifle.

Tar

Wrong a few counts there. The military shoots 62 grain M855 ammo generally and they have not used 55 grain ammo in a long time. The reason for 1/7 was to stabalize the tracer round that is very long. Its not bullet weight but rather length that makes a fast twist necessary. I don't personally care for 1/9 at all. Its not versatile in that it does not work well with heavy bullets. The 1/8 and 1/7 are much better and in my experience they have shot everything from 50 grain to 77 grain bullets well.

Pat

Edited July 26, 2012 by Alaskapopo

[Sleepswithdogs]

Guess I'm behind the times with the bullet weight. Here is something on twist rate you might find interesting:

"From the owner of ArmaLite, Ret. Lt. Col. Mark Westrom on the subject.

The Facts Behind the 1:7 inch twist AR barrel.

There's a lot of buzz around that the 7 inch twist barrel is just the thing for the AR family and that a 1:9 inch twist barrel is second rate. This isn't actually true, and ArmaLite's President, Mark Westrom, was deeply involved with the matter while a Civil Servant at the Armament Command at Rock Island. It's an interesting story.

In the early days of the M16A2 he received a message that Procurement was set to buy 155,000 M16A1 barrels just when the Army was switching to 1:7 inch M16A2 barrels. The problem wasn't merely poor accuracy or logistics; he was concerned that because the 1:12 inch twist barrels wouldn't stabilize the M855 well enough to prevent wounds that were likely to raise Geneva Convention complaints, it would make both legal and logistic sense to settle for a compromise barrel that would handle both.

He consulted with Col. (Dr.) Marty Fackler, he of the Army's Wound Ballistics Laboratory, who agreed with him and offered to run some pig cadaver tests to verify if a problem existed. Westrom sent the proper request and Fackler confirmed that use of the M855/865 bullets in the 1:12 inch twist left dramatic but somewhat less than effective wounds.

Westrom consulted with ammunition specialists at Picatinny Arsenal and proposed that even though 1:7 was required "to stabilize the M856 tracer" the 1:9 inch twist rate should be fine for both M193 and M855 ball rounds and would be good enough for the usual purposes of tracers: close in fire at night. He was surprised when he was told "No, 1:9 is actually pretty much optimal for the M856 tracer. 8.5" twist actually."

Upon further questioning he was told that 1:7 was used in the M16A2 because it was used in the M249 Squad Automatic Weapon. FN submitted the M249 with 1:7 inch twist and it won the SAW competition and was thus produced with that barrel. They didn't know why 1:7 was used in the M249. (It over stabilized those bullets, which led to decreased long- range accuracy and reduced barrel life.)

Westrom asked the authorities to call FN to find out why they used the odd 1:7 inch rate.

The next day Picatinny called back and said "You aren't going to believe this: FN remembered the accusations the US received over the cruelty of the early 1:14 inch rifling twist of the early M16." They used 1:7 inch twist so they'd never have to answer that complaint.

In other words, the 1:7 inch rifling twist was a political decision of a Belgian civilian, not a technical decision at all. As one foot follows the other, we've gone forward with the odd barrel.

So here's where we are today. 1:9 is great for M193 bullets and to around 70 grains. 8 inch twist is fine for bullets up to around 77 grains. Higher twist rates are sometimes used for even heavier bullets.

But these bullets aren't those used outside competitive shooting, and normally loaded one shot at a time. Some military ammunition uses a 77 grain bullet, but that's rare with commercial arms and is VERY hard on the bolt of the M16.

ArmaLite does make rifles with 1:7 inch twist for those contracts that require it, but for almost all military, police, and civilian use it's suboptimal.

Our customers learned this early on. Years ago ArmaLite sold 1:7 inch twist barrels and the market very much disliked them. It took a long time to sell them. The idea of a chrome-lined 1:7 inch barrel for match-type isn't very logical, but we'll build them when the customer demands.

The bottom line is though, that sometimes what the customer wants is driven by funny advertisements rather than technical facts. This isn't the only issue that falls into that area.

Westrom's idea is that DOD should switch to the 1:9 inch barrel for both the a1 and A2 rifles. He was allowed to convene a meeting on the topic and what followed stunned him. He was savaged for the idea, and this was by friends. He raises the issue later when another 120,000 1:7 inch barrels were being bought, to the same end.

One of his first actions at ArmaLite was to standardize the flexible 1:9 inch rate."

Edited July 26, 2012 by Sleepswithdogs

[grouse]

If that is true, that is very interesting. Thanks for sharing.

[Alaskapopo]

Frankly anything coming from Armalite to sell their products (1/9 twist guns mostly) is suspect with regards to them recommending one twist over another. This is from ammo oracle

START QUOTE

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.

Opinions (Pro and Con):

1:9 is best.

Why? Flexibility. It doesn't seem to have any problems throwing M856 tracers around, unless it gets really cold, it wears better than 1:7 and it stabilizes more rounds than 1:12. Additionally, 1:9 rifles, even Mil-Spec chrome chambered and barreled, can attain 1.0-2.0 MOA out to 300+ meters.

No, 1:7 and 1:8 are the best.

Why? Accuracy. For heavier and longer rounds during competition shooting, 1:8 and 1:7 twists are the best for heavy 77-80 grain rounds that I use to shoot competitively at 500-1000 meters. Who needs to shoot tracers anyhow? More importantly, heavier rounds are showing very good results in terminal testing and are proving to be much better defensive rounds.

END QUOTE

As to my personal experience. 1/9 twist guns are fine if you want to limit your self to shooting 50 to 70 grain bullets. I don't want these limits. I have found my 1/8 and 1/7 twist guns shoot bullets from 50 to 77 very well. I prefer the heavy bullets for long range stages and for anti personal uses in the real world. The heavy bullets have much better terminal performance. So rather you are builing a gun for the game or for the real world your better off with a twist rate that does not limit your bullet options on the heavy side.

Pat

[MickB]

If you want 16", mid-length gas, chrome lined, threaded end, then go with Daniel Defense.

I went with their lightweight "pencil" barrel for a lightweight build for my son.

It is 0.625" inder the handguards. Gas block area is smaller than 0.750", however. I got mine with a pinned on Daniel Defense low profile gas block.

If you want adjustable gas, Syrac makes their gas block in a version to fit the pencil barrel....

Mick

Edited July 27, 2012 by MickB

[kurtm]

Criteria barrels are your answer!! Best kept secret in 556x45 barrels today especially with chrome lining.

One thing all you " barrel cowboys" are missing is the velocity factor. Pat has a point EXCEPT IN 20" barrels. I haven't found a 1x9 20" that wont do AT LEAST 2 M.O.A. with 75/77 gr. Bullets......because the velocity is almost 100 fps. Faster. Slower twist with faster velocity= slower velocity/faster twist. A 1x9 is just fine in longer barrels with "heavies", but what the heckl do you need them for? If I'm going to shoot "heavies" it has to be at something like a pig, not steel.

[Alaskapopo]

Criteria barrels are your answer!! Best kept secret in 556x45 barrels today especially with chrome lining.

One thing all you " barrel cowboys" are missing is the velocity factor. Pat has a point EXCEPT IN 20" barrels. I haven't found a 1x9 20" that wont do AT LEAST 2 M.O.A. with 75/77 gr. Bullets......because the velocity is almost 100 fps. Faster. Slower twist with faster velocity= slower velocity/faster twist. A 1x9 is just fine in longer barrels with "heavies", but what the heckl do you need them for? If I'm going to shoot "heavies" it has to be at something like a pig, not steel.

What your saying is correct I did not think of it as a velocity issue as much as the longer barrel has more time to stabalize the bullet in a 20 inch barrel vs a 16 inch one. I had a 20 inch Saber Defense A2 build I did and it did shoot fine with 77 grain bullets with its 1/9 twist barrels. Its hit or miss with 1/9 twist barrels and heavy bullets. I think 1/8 is the best twist going overall. I still like the heavies for the long range stages. They have given me better accuracy than the lighter weight bullets. I do limit my use of the 77 grain bullets to past 200 yards however to save on cost.

Pat

[kurtm]

We agree my Northern friend... I really like 1X8 in a barrel especially in a 20"!