Ar Barrels: Get What You Pay For?

[The Rabbi]

As mentioned elsewhere, I am looking to build my own AR carbine. I am overwhelmed by the variety of barrels on the market. Some are 1 in 9 twist, some 1 in 7. Some are button rifled (whatever that is). ome chrome-lined some not chrome lined. Some are chambered for .223 Remingon and some for 5.56 Nato. Some are about $125 and some are about $400.
Can anyone clear up some of the mystery here so I can make an intelligent choice? I am looking for a 16" barrel for plinking but also maybe some serious target work.

 

[mtnbkr]

I too am in the process of building my first AR.

Here's what I've learned:

.223 vs 5.56: similar cartridges, but the 5.56 needs a longer throat. Can fire .223 in 5.56 chamber and sometimes vice versa, but sometimes 5.56 in .223 chamber will result in higher pressures. If you're shooting surplus ammo, go 5.56, if you want best accuracy with premium ammo or handloads, go .223.

chrome vs non-chrome: chrome resists corrosion. If you want a lower maintenance gun, go chromed. non-chrome can be more accurate, but you'll need to maintain your gun like any other rifle.

1 in 7 vs 1 in 9: 1 in 7 is better for lighter bullets. 1 in 9 is the compromise, I think 1 in 12 is for the heavier bullets.

I'm going with a 16" chromed barrel with a 5.56 chamber and 1 in 9 twist because this one's going to be a plinker. If I build a .223 for accuracy, I'll go non-chromed, .223 chamber, and a twist rate better suited to the bullets I want to use. That said, my next upper is likely going to be either a 300whisper or 50beowulf anyway.

Based on what you say you'll use it for, I'd go .223 chamber, non-chromed bore/chamber, and a twist rate suited to your choice of bullets (1 in 9 if unknown at this time). I don't know about button rifling, brands, etc...

Chris

 

[ShootAndHunt]

in 7 vs 1 in 9: 1 in 7 is better for lighter bullets. 1 in 9 is the compromise, I think 1 in 12 is for the heavier bullets.

No, the tighter the twist rate, the heavier bullets it could handle, so 1 turn in 7 inchs is for the heavier bullets.

 

[mtnbkr]

No, the tighter the twist rate, the heavier bullets it could handle, so 1 turn in 7 inchs is for the heavier bullets.

Sorry, got it backwards.

Chris

 

[ocabj]

I am looking for a 16" barrel for plinking but also maybe some serious target work.

That's somewhat of a contradictory statement. If you want a 16" for plinking, then get a 1 in 7" with a 5.56 NATO chamber. It'll let you shoot most any .223 caliber bullet weight and the 5.56 chamber will let you shoot Winchester Q3131A, Federal/LC XM193, or any other 5.56 NATO spec cartridge as well as regular .223 Remington ammo.

But we are, afterall, talking about an AR, so you can always buy seperate upper receivers. Get the 16" 1 in 7" 5.56 NATO upper and then get a 20" 1 in 8" .223 Match/Wylde upper. Much fun.

 

[Mulliga]

In general, yes, you do get what you pay for.

If you spring for a nice Krieger barrel, for example, it'll certainly shoot better than a $125 barrel from who-knows-where. If you spring for a Bushy 4150 chrome-lined 5.56 barrel, it will be tough as nails and will certainly outlast the average shooter. Of course, the same is true of most AR barrels, but if you're building an AR yourself, why not go with the best now rather than having to upgrade later?

 

[444]

Well, if you want a specific recomendation, you are going to have to be much more specific. The problem with most of these threads is that the person posting wants the best possible gun for every possible purpose and that isn't really possible. If you want an AR to use as nothing more than a plinker, then any barrel including the cheapest one available will work and you will probably be perfectly happy. If you are really going to use the AR for serious target competition then you are going to need a completely different barrel and it most likely won't be in 16" length. For a good, general purpose, rugged, reliable 16" barrel, I would go with one chambered for 5.56mm with chrome lining, and a 1:7 twist. Why ? As was mentioned, the 5.56 chamber will be more reliable with any ammo you are likely to encounter. It will also be more tolorant of dirt. In other words, it is more versitile. Military M16s use 5.56 chambers. I would go with a chrome lined barrel. Again, more reliability and some increased duribility. Military M16s use chrome lined barrels and chambers. 1:7 twist. When the M16 was first designed, it used a 1:12 twist and 55 grain bullets. Today, we are using heavier bullets to retain more energy and be less effected by wind. With a 1:7 twist, you are going to be able to shoot bullets weighing perhaps 80 grains. With a 1:9 you won't be able to stablize the heavier bullets. The Mil-Spec is 1:7.
There is no one barrel that is going to give you the best possible performance under every possible situation. I believe the barrel I recommended will give you the most versitility and best performance under any use short of serious formal service rifle competition. And, there is no free lunch, or as you put it, you get what you pay for: just like everything else in the world. You buy a cheap, no-name, almost as good as.... you will more than likely regret it: assuming you are actually going to be using it enough to make it's shortcomings evident.

 

[Slater]

Some good info here:


http://www.ammo-oracle.com/body.htm

.

 

[Bartholomew Roberts]

As mentioned elsewhere, I am looking to build my own AR carbine. I am overwhelmed by the variety of barrels on the market. Some are 1 in 9 twist, some 1 in 7.

1/9 will let you shoot anything from light 45gr varmint loads all the way up to 69gr match loads. Some people have success with 1/9 barrels and heavier 75gr and 77gr match bullets; but accuracy usually suffers and it can be iffy.

1/7 will let you shoot anything from 52gr to 77gr (and even special single-loaded rounds like the 80gr VLD) with no problems.

Some are button rifled (whatever that is). ome chrome-lined some not chrome lined.

Chrome-lining will require less maintenance than a non-chrome lined barrel but are less accurate. Unless you can already shoot sub-MOA groups, you are unlikely to notice the difference between a good chrome-lined barrel and a good non-chrome-lined barrel. More important that whether the barrel is chrome-lined or not is that it is a quality barrel to begin with.

Some are chambered for .223 Remingon and some for 5.56 Nato.

As described earlier, a 5.56mm chamber has a different throat and can fire both .223 and 5.56. A .223 chamber is tighter and firing 5.56mm will generate higher pressures that will affect functioning and in extreme cases can be unsafe. There is also a chamber called .223 Wylde that is a kind of in-between version.

If reliability is your primary concern, you are best off with the 5.56mm chamber. If accuracy is your primary concern, a .223 chamber will be tighter. Again, unless you can already shoot sub-MOA, you probably won't appreciate the difference in accuracy much.

Some are about $125 and some are about $400. Can anyone clear up some of the mystery here so I can make an intelligent choice? I am looking for a 16" barrel for plinking but also maybe some serious target work.

If you want to print 5-shot groups less than 1" at 100yds, then you might want to start looking at the higher end non-chrome lined barrels with a .223 chamber or Wylde chamber. If your accuracy requirements are less demanding than that, then a chrome-lined 5.56mm barrel will give you the longest life and require less maintenance while still delivering acceptable accuracy. If you want to use some of the heavier bullets popular for defensive use, a 1/7 or 1/8 twist is necessary. If varminting is more your interest, you'd be better served with a 1/9.

My 16" 1/9chrome-lined 4150 HBAR w/5.56mm chamber from Bushmaster manages 1.5-2" 5-shot groups regularly and is capable of 1" 5-shot groups @100yds with shooters and ammo it likes. I've even managed the occasional sub-MOA group; but that is more of an oddity than a regular occurence.

 

[30Cal]

If you've run into the brick wall and can't seem to get your name on the top of the match results, then I'd seriously consider the best barrel money can buy.

Otherwise, get the chrome lined barrel and spend the rest on ammo. Have a good time!

Ty

 

[Quintin Likely]

A lot of the hubbub with barrels depends on the person who chambers and headspaces it as well. A 16" tube can be plenty accurate, but it is kinda counter-intuitive to max accuracy, since you're getting less velocity and a shorter sight radius if you're using iron sights. And, well, accuracy means different things to different folks; to some, it's putting 3 or 5 or more shots into an area the size of a quarter or so at 100 yards, to others it's consistently holding a 6 inch X-ring at 600 yards, to others it's knocking the lights out of Mr. Prairie Dog way out in no-man's land.

As far as twist rate goes, I think a 1:8 is probably the most versatile, letting you shoot anything from the 40-something grain gopher busters to (provided the throat on your rifle is long enough) 80 grain match bullets.

Cut rifling is when a single point cutter is driven through the bore, cutting the grooves. Then there's button rifling, where a swage is pulled through the bore, forming the grooves. I think you'll probably start a fight discussing which is better and why amongst different barrel makers though. I don't shoot good enough to tell the difference.

5.56 NATO chambers have longer throats and are generally more forgiving of different kinds of ammo. There's a few speciality chambers as well, like the Wylde chamber which I think is longer than a .223 but shorter than a 5.56, I think CLE has their own and there's one for Pac-Nor 6.5 twist barrels too. For a plinking, general use, knockabout gun, get a 5.56 chamber and forget about it. Most major AR makers (I know Bushmaster does) chamber their "normal" barrels in 5.56 anywho. I'd go chrome lined on a general use gun and non-lined on something for outright accuracy as well.

 

[Coltdriver]

Rabbi you have seen some posts above talking about the benefits of the tighter twist barrels.

However, just to confuse things, the original .223 (and M16) came in 1 in 12 twist and will stabilize a 55 grain bullet out of a ~20 or 22 inch barrel just fine. It makes a great 200 yard round. The other benefit is that you can also propel some of the lighter bullets at great speed and have a real nice 235 yard point blank range rifle. I shoot a 1 in 12 twist barrel and have some dandy 40 and 50 grain varmint loads. Those are ~3400fps rounds that shoot 1 inch high at 100 yards and hit at 235 yards 1 and a half inch low.

That being said, a 1 in 7 may very well over spin a 40 grain bullet above a potential velocity. And shooting heavy bullets at long distances you are not talking about a flat shooting round with a .223. I have not calculate the arc on a 77 or 80 grain .223 at 300 yards but I am pretty sure it is substantial.

The most common and cheapest bulk ammo is going to be your 55 grain variety. The barrel the military went to in order to better stabilize the 55 grain nato rounds was a 1 in 9 twist. I would definitely go for the 5.56 chambering as you can safely shoot either type.

 

[wanderinwalker]

That being said, a 1 in 7 may very well over spin a 40 grain bullet above a potential velocity. And shooting heavy bullets at long distances you are not talking about a flat shooting round with a .223. I have not calculate the arc on a 77 or 80 grain .223 at 300 yards but I am pretty sure it is substantial.

Depends on how we define substantial. No, it isn't lazer-flat like a 40gr varmint bullet at 3500fps. Between 200 and 300 yards a 77gr .223 drops between 6 and 9 inches from a 200 yard zero, depending on rifle/shooter/velocity levels. When we get to 600 yards, the drop on an 80gr bullet with a BC or around .440, is 6 FEET from a 300 yard zero. But the wind-drift is less severe. BTW, these are calculated with a launch speed of 2600fps, which can be beaten by between 100 and 150fps, again depending on the exact mix of rifle/powder/barrel/bullet/primer/case/chamber.

At any rate, for a plinker AR, I would go with the above suggested 1-9 twist with a 5.56 chamber. Go chrome-lined for peace of mind and then just go shoot. Plus, as has also been mentioned, if you decide you want a different barrel/caliber/sight configuration on your AR-15, just plug-and-play!