# AR barrel length 101



## budgetprepp-n (Apr 7, 2013)

I'm thinking about the ARs that are used for shooting a little bit if distance.

For an upper I'm sort of stumped on something. The longer barrel must be something that's needed I see a lot of them on ARs for shooting a longer distance............Why?

Dose the longer barrel give more "burn time" to the powder so the bullet can accelerate to maximum speed in the barrel?

Or dose it somehow stabilize the bullet better because of being in the barrel longer ?

I see barrels made of chrome steel, Stainless steel Or chromed lined what is best? And why?

And they list how many groves there are. I'm assuming that the groves are cut into the barrel? How does the number of groves relate to the speed of the twist? 

I have learned a little about twist rate and if I'm correct I'll be needing a fast spin rate and a heavy bullet?
Maybe spin 1-7? ,,,,,,,,,,,,,,,,,,,, bullet 62 and +? 

Boy, I never realized how much goes into the making of a barrel until I started asking questions about it

I hope you don't mind answering questions that must seem basic to you. 
You know I bet more than just a few people wonder about the same thing but never ask.


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## Mad Trapper (Feb 12, 2014)

A longer barrel will give you higher velocity up to a point with a given load. It also gives a longer more accurate sighting plane if you are shooting open sights

There are various types of rifling and that includes the number of lands and grooves, and their depth. The twist needs to be faster as you increase bullet mass in a given caliber.

Not experienced with AR platform but these variables should all be worked out and I'd shop barrels from quality makers.

Another thought is do you want 5.56/223 or something else?


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## SOCOM42 (Nov 9, 2012)

Deleted.


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## Chipper (Dec 22, 2012)

I would worry more about the cartridge you choose to shoot then barrel length. The varmint cartridge 223/556 would be the last one I'd pick for long range work. 6mm, 6.5 or 30 caliber would be better unless you consider 300 yards long range.


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## dwight55 (Nov 9, 2012)

A friend gave me a 26 inch, 1/7 twist, medium weight, stainless barrel that is Wylde chambered, . . . meaning it'll take either 5.56 or .223, . . . and say thank you.

It was a "cast off" from a 600 yd shooter for whom my friend is the gunsmith. 

I've had no real issues dropping 15 out of 15 in a 2 inch by 2 inch center square, . . . at 100 yds.

Apparently that length and twist is great for 5.56, . . . common, . . . military grade, . . . surplus ball ammo.

Anyway, . . . when I get back "well", . . . it's gonna get tried by me at my max on my range, . . . 200 yds, . . . and I expect it to do well.

May God bless,
Dwight


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## Smitty901 (Nov 16, 2012)

The difference between a 16 and 20 is not enough to be concerned with. The only real advantage with a 20 inch and iron sights is the distance between sights. The great that distance the more accurate you can be. That can also be over come for the most part.
I have 16, 18 and 20 inch. The only thing I would get real excited about a 20 inch would be shooting 55g with a 1 in 11 or 1 in 12 twist. But then again not a real big deal.

Any Ar chambered for 5.56 will shoot .223 safely. How ever it loses a little accuracy doing so. Wylde chambered over comes that slight down side and fire both with out and real loss.


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## AquaHull (Jun 10, 2012)

M193 out of a 20" 1:12 twist rocks.


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## RedLion (Sep 23, 2015)

I agree with what has been said to this point. I have AR's with 14.5", 16" and 20" barrels. I still have an affinity for 20" AR's for the reason mentioned already.


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## LunaticFringeInc (Nov 20, 2012)

For long range shooting....

I would choose a 20 inch barrel for that task. There aint that much speed lost using the 16 inch barrel but it is a bit and if your shooting long range you want that extra 100 fps or so it gives you. Think about it does 4 mire inches of barrel really add that much more weight or make it all that more cumbersome to carry around? If you are that sensitive to weight get it deeply fluted which would also help stiffen it up too as well. Besides aint that the original length of the barrel on the AR as designed to begin with? I am willing to bet there is a reason that length was chosen by the manufacture and the military although at the time the ammo was supposed to be 55 grs. One thing I can definitely tell you there is a very noticable drop in velocity on a 14.5 in M4 and my 20 in AR, I dont care what the bullet weight is.

When it comes to accuracy I would seriously consider the quality control in the barrels manufacture even more and its tolerances as thats going to likely be a bigger effect on accuracy than 4 more or less inches of barrel.

Another thing to consider is that a faster velocity doesnt always equal accuracy. Often times the best load in a rifle is not the slowest or the fast velocity but something inbetween. Just like on a base ball bat. there is gonna be a sweet spot somewhere on it and thats where you wanna hit that ball! What faster velocity will get you with a good bullet is a little flatter trajectory and a little more range before it goes sub sonic on you at which point you "fall off the cliff" from a accuracy stand point.

Chrome lined barrels are more for reliability, corrosion control and ease in cleaning. I would get a quality SS barrel.

My guns are wearing a 1-9 twist. I have found that anything from about 53 grs depending on the bullet to 69 grs SMK's to be what my guns shoot best. I have herd people getting decent results with heavier bullets but I am not seeing that in my guns. Maybe I got a lemon but it will put those 69gr SMK's into a .38 inch 5 shot group! I am thinking you want at least a 1 in 8 and probably a 1 in 7 for what you want to do. As for rifling talk to your barrel maker they can help you out with that. I know when I had a 28 inch barrel for my 224 TTH on a mauser action, 1 in 6 was the sweet spot using 80gr bullets at 3650-3700 fps, I wasnt disappointed. Bullet weight/velocity and barrel length will play a factor in what twist rate you need to use.

The type of rifling I think aint a huge deal, not nearly as much as How well and how close are the toleraneces on the rifling. I have herd great things about the 5R rifling Remington is using but dont have any guns like that to compare it to. So I dont know other than get tolerances as tight and as smooth as possible.

Yeah if your getting a custom made barrel there are a lot of things to consider and weigh in on!


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## RedLion (Sep 23, 2015)

I get moa at 100 yards with my 1:7 twist 14.5" BCM SOCOM barreled AR using a Vortex Strikefire II red dot. It is a tack driver.


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## Hemi45 (May 5, 2014)

I have barrels in 14.5, 16 and 20 inches. All are 5.56, 1:7 twist and chrome lined (as are the chambers) because its more durable and forgiving of quickie cleanings. That said, if you wanted a tack driver that allowed for the widest range of bullet weights I'd opt for a 20" stainless bbl with a 1:8 twist chambered in .223. The one tradeoff I personally would make is going with 5.56 to allow for more ammo versatility.


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## SGT E (Feb 25, 2015)

I got a Bushmaster Varminter in 24 inch barrel and a 6.6X20 Vortex on it and its pretty wicked on ground hogs out at 500 yards

I just built an AR with an ER Shaw 24 inch stainless bull barrel in 1 and 8 twist and it shoots even better! E.R. Shaw Custom Barrels | E.R. Shaw Custom Barrels | E.R. Shaw Inc. | Makers of Precision Gun Barrels and the E.R. Shaw Mk. VII Custom Bolt Action Rifle.

Krieger barrels in a 1 and 7 twist will take it a tad further.

https://www.kriegerbarrels.com/ I happen to own two bulls in 24 inch stainless in 1 in 7 twist...cost is worth every cent!

Take your time...Don't Scrimp on anything even if it takes you a year to build it! Ask questions and do a lot of research!


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## AquaHull (Jun 10, 2012)

My 20 " NOS Colt A1 barrel was close to $300

Shooting M855's in it is a hoot, as well as a prayer


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## budgetprepp-n (Apr 7, 2013)

SGT E said:


> I got a Bushmaster Varminter in 24 inch barrel and a 6.6X20 Vortex on it and its pretty wicked on ground hogs out at 500 yards
> 
> I just built an AR with an ER Shaw 24 inch stainless bull barrel in 1 and 8 twist and it shoots even better! E.R. Shaw Custom Barrels | E.R. Shaw Custom Barrels | E.R. Shaw Inc. | Makers of Precision Gun Barrels and the E.R. Shaw Mk. VII Custom Bolt Action Rifle.
> 
> ...


When someone refers to a barrel as a "BULL BARREL" ,,, What does that mean?


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## KUSA (Apr 21, 2016)

For a fighting rifle I would get a cold hammer forged, chrome lined 16 inch barrel, 1 in 7 twist with a 5.56 chamber. Daniel Defense makes a great CFH barrel. 

For a varmint or target rifle I would get a 20 or possibly a 24 inch barrel made of stainless that had cut rifling such a a Bartlein. I would go for a 1 in 7 or 1 in 8 twist and a match chamber.

Now you need to learn about the gas system as in carbine, mid, rifle.


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## KUSA (Apr 21, 2016)

budgetprepp-n said:


> When someone refers to a barrel as a "BULL BARREL" ,,, What does that mean?


It means that it is very thick like 1 inch in diameter. Very heavy.


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## Smitty901 (Nov 16, 2012)

If budget supports it a gas piston may serve you very well and a lot easier to maintain. As for chrome lined vs Melonite. Chrome process is old news was out done by Melonite process. It was used before chrome process but was difficult and expensive. Modern times over came those issues. Either one will serve you well neither is a must have over the other.


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## SGT E (Feb 25, 2015)

KUSA said:


> It means that it is very thick like 1 inch in diameter. Very heavy.


This place has same barrels/ ER Shaw Bull Barrels.....Pics also! 
https://www.model1sales.com/index.c...onid=E4F5B831B52A734DA24C8F8DFD4EABAD.cfusion








Barrels are .938 Diameter!

I buy solid stainless....No fluting...No removal of metal. May take a while for a non fluted barrel to cool down but at 600 yards you don't need to shoot as much!


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## budgetprepp-n (Apr 7, 2013)

KUSA said:


> For a fighting rifle I would get a cold hammer forged, chrome lined 16 inch barrel, 1 in 7 twist with a 5.56 chamber. Daniel Defense makes a great CFH barrel.
> 
> For a varmint or target rifle I would get a 20 or possibly a 24 inch barrel made of stainless that had cut rifling such a a Bartlein. I would go for a 1 in 7 or 1 in 8 twist and a match chamber.
> 
> Now you need to learn about the gas system as in carbine, mid, rifle.


Ok I'll get to that soon enough,,But for now I'm still learning about barrels,, I had no idea a barrel had so many options to factor in. 
Very informative stuff.


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## budgetprepp-n (Apr 7, 2013)

From what you guys are saying so far the barrel on my AR is a 16" w/ 1-7 twist - Stock Colt -
And that barrel should be good for a ways farther than 100 yards.


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## KUSA (Apr 21, 2016)

budgetprepp-n said:


> Ok I'll get to that soon enough,,But for now I'm still learning about barrels,, I had no idea a barrel had so many options to factor in.
> Very informative stuff.


The gas system is part of the barrel. It starts with a tiny hole drilled in a specific spot on the barrel. Some manufacturers drill the hole too big and over gas the gun.


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## KUSA (Apr 21, 2016)

budgetprepp-n said:


> From what you guys are saying so far the barrel on my AR is a 16" w/ 1-7 twist - Stock Colt -
> And that barrel should be good for a ways farther than 100 yards.


With the right ammo you should be able to hit torso sized targets at 500 yards consistently.


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## AquaHull (Jun 10, 2012)

budgetprepp-n said:


> From what you guys are saying so far the barrel on my AR is a 16" w/ 1-7 twist - Stock Colt -
> And that barrel should be good for a ways farther than 100 yards.


Yes leave it alone, and build the next one up.


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## RedLion (Sep 23, 2015)

budgetprepp-n said:


> From what you guys are saying so far the barrel on my AR is a 16" w/ 1-7 twist - Stock Colt -
> And that barrel should be good for a ways farther than 100 yards.


Don't limit yourself to a colt. BCM, Faxon Firearms and Aero Precision are a few of several good manufacturers with good products. Palmetto State Armory has top shelf stuff as well. Their premium carbine has been listed for about $750 lately. Everything that you would want in a carbine. PSA 16'' M4 Premium Carbine


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## RedLion (Sep 23, 2015)

KUSA said:


> With the right ammo you should be able to hit torso sized targets at 500 yards consistently.


And practice using proper techniques along with good ammo will allow you to do so.


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## Smitty901 (Nov 16, 2012)

Colt is a fine AR the LE6920 set the standard. However as in all things times change. There are many as good or even better on the market at fair prices.
Few people today even want an A2 style AR.


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## Smitty901 (Nov 16, 2012)

A trained a practiced shooter can depending on eye sight and practiced skills hit a man size target with an AR15. It would remove no special ninja sniper skills or equipment. Master gunners using an AR with spotters do hit 1000 yards with an AR. Understand they are very well trained and practiced. It is also done with the aid of ACOG scopes and a spotter on a know distance range. Also at that range the 5.56 or .223 has little penetration left.
Few will ever even get a chance to target a man size target at 500 yards anywhere but on a range.
A trained shooter is someone that has had hours on hours of instruction for a qualified person, and has demonstrated the skills they have been instructed in. Practiced is a shooter that has demonstrated they have kept those skills current by demonstrating them to a well qualified Person.
Keep these facts clear: Chrome lined or Milonite is not an issue. A weapon chambered for .223 only is not safe for a 5.56 the pressure of the 5.56 can cause round to swell and stick. A weapon chambered for 5.56 will fire .223 safely. A Wylde chambered weapon fires the 5.56 and .223 equally well. It is becoming more widely know even though it has been around a long time. 1 in 7,8,9. Your call The difference has little effect on most shooters using the rounds they are likely to shoot and the ranges.
There are two types of AR operating systems The most common is DI (direct gas), the other is gas piston. Each has advantages and disadvantages. Cost being one of the down sides to the piston. Barrels SS stands up to nature much better, Non SS tend to wear a little better long term. Few will ever put enough rounds down one to find the difference. 
If you are looking at one to buy and it has an A2 front sight, and you know that is not what you want pass it buy and get what you want. The cost and effort in changing it over will likely cost you more in the end. Furniture for an AR can get costly. meaning changing to a free float rail, pistol grip , butt stock. Low profile gas blocks. Different sights and scopes.
Do you want this? Unmolested Clot Ar15 LE 6920








This or something in between best to know before you buy it can save you a lot of cash and heart ache.








This is fairly accurate and should give some information to work with. It however was made before the 5.6 became the most common and leaves out some facts. Military does not ever issue 55gr anymore. As a rule any 5.56 over pretty much 77gr will need to be loaded one at a time they will not fit the magazine. 80gr is considered to be the absolute limit . Now some ninja customer loader is going to claim to have made 90gr work. consider the source .








Good luck First AR is a journey the second , third ... is just the next road in the journey.


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## budgetprepp-n (Apr 7, 2013)

Smitty901 said:


> Colt is a fine AR the LE6920 set the standard. However as in all things times change. There are many as good or even better on the market at fair prices.
> Few people today even want an A2 style AR.


 With the prices in today's world the LE6920 can be bought for $700 i just bought one that has a law enforcement on one side and S.D.N. MEXICO D.F. On the other side.
It came in the box with a carry handle

I probably miss some good deals I don't know about a lot of brands so when I buy a gun I go for a colt and if I need a scope I get a Leupold.
I stick with what I know is a proven brand. Maybe I need to start reading and looking at other brands.


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## AquaHull (Jun 10, 2012)

BCM and Danny Defense are good brands


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## Smitty901 (Nov 16, 2012)

budgetprepp-n said:


> With the prices in today's world the LE6920 can be bought for $700 i just bought one that has a law enforcement on one side and S.D.N. MEXICO D.F. On the other side.
> It came in the box with a carry handle
> 
> I probably miss some good deals I don't know about a lot of brands so when I buy a gun I go for a colt and if I need a scope I get a Leupold.
> I stick with what I know is a proven brand. Maybe I need to start reading and looking at other brands.


 Leupold would not be my choice for an AR but that is why there is more than one brand. You can't go wrong with a Colt. Those stamped ones were made for export to Mexican government and for what ever reason were never shipped.
When it was time to purchase one for my Daughter Colt was what she wanted and that is what she got. That was some time back, hers now has the A2 front sight removed. The Colt standard hand guards are gone and she has a 13 inch K mod free float rail.
Good luck with it , should serve you well. The LE stamp was a hold over from the Brady Bill days.


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## budgetprepp-n (Apr 7, 2013)

STG E Said, I buy solid stainless....No fluting...No removal of metal. May take a while for a non fluted barrel to cool down but at 600 yards you don't need to shoot as much!

The fluting done on a barrel helps it cool down faster? Fluting gives more surface? The idea is the same as cooling fins?


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## Alteredstate (Jul 7, 2016)

budgetprepp-n said:


> When someone refers to a barrel as a "BULL BARREL" ,,, What does that mean?


This designation has a variation to it as everything does. A typical mill spec barrel has narrow locations where the military planned barrel failure. The volts years ago had a barrel marked heavy or some b.s. stamped in the steel. It does not have the relief cuts that a mil spec cut barrel has. A bull barrel in my opinion would have more mass than the uncut heavy barrel. The total mass of the barrel when it is heavy adsorbs more heat and remains more ridged.


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## Smitty901 (Nov 16, 2012)

The fluted barrel is to light the weapon. Heavier barrels take longer to heat up to a point is has an in pack on accuracy. The design of the lighter AR barrels was intend to split the difference. Think Military infantry soldier , weight save weight every where you can.
A concern that is addressed in every think they carry.
No one planned barrel failures on an M4 never seen on fail. If you would like to see one that had a round jam an a second round followed and jammed both No damage to any part of the weapon other than two rounds stuck in a barrel I have it sitting here.
There are down side to custom loads.


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