AR-15 barrel profiles

You might want to swing by ar15barrels.com. Lots of good info there.

I don't have the measurements handy but in general, here's what they are:

Lightweight - thin the entire length.
government - thin under the handguards, heavy profile from the gas block to the flash suppressor
M4 - stepped barrel, thin under the handguard.
A1 - generally a lightweight barrel, whole length.
A2 - generally a government profile, sometimes an HBAR
HBAR - very heavy under the handguards, heavy to the FS.
standard - heavy all the way to the FS.
Pencil - thin the entire length.

For a handy carbine, get a lightweight barrel. They are accurate, unless you shoot the living crud out of them and get them super hot, and the weight savings is worth it. There are no downsides to light barrels, unless you're shooting F/A or match shooting.

The lightweight/pencil bbl should work fine for you. Right now I have a carbine with it that weighs in about 5 pounds unloaded. You could probably get even lighter with a Cavalry Arms lower receiver.

Just keep in mind what swingset says about lightweight barrels. Accurate, but they are not something you are going to want to blast away with. If your looking for a "Dump a 20 round magazine into the side of the hill as fast as possible" gun, don't go lightweight. If your thinking more along the lines of a target or varmint gun, then you should be fine.

"Dump a 20 round magazine into the side of the hill as fast as possible" gun, don't go lightweight.

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Doing so surely won't hurt the gun, anymore than it hurts a heavy barrel, but by the 20th round your groups will open up. Of course, if you're blasting into a hillside, you're not going to care or notice that you're now shooting 3" groups instead of 2" groups.

Truth is, unless you're match shooting or going Full Auto, you will never notice a difference. Heavy barrels are for most shooting situations, entirely useless.

Heavy barrels are for most shooting situations, entirely useless.

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In terms of first-shot accuracy, that's probably true. In terms of handling - maybe not. A heavy barrel won't make transitions as fast as a lighter barrel, but it often stabilizes better offhand and gives better practical accuracy as a result. Certainly, a heavy barrel will 'rest' better and be easier to shoot off of bags/bipod.

I shoot most of my rifles in the field (no CQB) offhand using a hasty sling, and as a result I like my ARs to balance just forward of the mag well. If I'm building a 16" rifle, that may mean using a heavy barrel (heavy under the handguards). If it's a 20" or 24" rifle, that may mean using a lightweight or a fluted barrel. Each rifle gets a different barrel contour depending on what it'll take to make it balance.

As always, YMMV.

The lightweight or pencil barrel profile is the original M16A1 profile and IIRC is 0.675" in diameter under the handguards and forward to the flash suppressor. Weight is around 2.2lbs for a 20" barrel.

A Government profile is 0.675" under the handguard and 0.750" from the front sight base to the flash suppressor. Weight for a 20" in 2.5lbs. This is the profile the A2 uses.

Heavy barrel is a commercial barrel profile. As a commerical profile, there really isn't a set standard for HBAR. Generally, it is thicker than 0.750" underneath the handguards and 0.750" from the front sight base forward. Weight on a 20" barrel would be 3.0lbs.

Another one is "medium profile". It is another commercial product with no set standard; but generally it is around 0.750 from front to back.

Generally, unless you are going for extreme accuracy, the only thing you notice between a lightweight barrel and heavy barrel is the extra weight and handling change.

I pulled this info off the Bushmaster website. I picked up a Bushmaster superlite upper to go with my Bushmaster lower recently. Can't tell you how well it shoots yet longterm, (only put 30 rds through it so far), but, I like the way it handles and at 75 yds I put 10 rds into an apple sized group w/ the iron sights. Not bad for not having shot iron sights in years.

Barrel Weight In Pounds ( for milled front sight subtract 0.2 pounds )

Barrel length_________Heavy Barrels________ Fluted Barrels

10"_________________2.0_________________1.9
11.5"_______________ 2.2_________________2.0
11.5/5.5"____________ 2.6_________________2.5
14.5"_______________ 2.5_________________2.2
14.5"AK_____________2.7_________________2.4
14.5"MY_____________2.7_________________2.4
14.5"AM (phantom)____2.7_________________2.4
14.5"IZ______________2.7_________________2.4
16"_________________2.7_________________2.3
16" Dissipator________ 3.0_________________2.6
20"_________________3.5_________________3.0
24"_________________3.9_________________3.1
26"_________________4.0_________________3.2

Military Style Barrels

14.5"M4_____________2.0
14.5"M4AK__________ 2.2
14.5"M4MY__________ 2.2
14.5"M4AM (phantom)_ 2.2
14.5"M4IZ____________2.2
16"M4 Dissipator______2.3
16" Superlight________ 1.9
16"M4_______________2.2
20"A2 (govt profile)_____2.5



And, Weights of our Upper Receivers...
A1 Type - 0.7 lbs.
A2 Type - 0.8
V Match (flat-top, also designated as A3 type) - 0.6
A3 - 1.2 (including weight of A3 Type Removable Carry Handle)
A3 Type Removable Carry Handle only - 0.6

Heh. He has the same question I do. I'm looking for a flat-top upper, 16" chrome-lined lightweight bbl, A2 FH, standard sight tower, midlength. Bayo lug optional, but a nice feature.

Looks like www.ar15carrels.com will make a custom upper for you with that setup. RRA does not offer that option (wish they did). Beyond that...

Mike

Strangely, I couldn't find anyone who makes a 16" lightweight barrel. CMMG makes a 14.5" midlength lightweight chrome-lined barrel; but not a 16". I guess you would have to get a 16" chrome-lined midlength and have it reprofiled in order to get a 16" lightweight mid.

Or you could get a gov't profile 16" midlength... a couple of people make those in chrome-lined versions.

You can only get AR lightweight barrels in chrome-moly or Cr-Mo-V. Nobody will make a light profile stainless barrel for fear of what will happen to it when someone ignores the fact that stainless doesn't have the same heat resistance and does a beta-C dump through one. You might be able to get one custom; but I don't know anyone who wants the potential liability.

Take a peek at ADCO. http://www.adcofirearms.com/shopservices.cfm?page=shop They have crazy hours, but I've only heard of good about them.

Another option is Kurts Kustom, KKF. He does great work and I've sent a couple of guns to him. The only thing is that unless things have changed, you can expect a month or so wait.

I guess you would have to get a 16" chrome-lined midlength and have it reprofiled in order to get a 16" lightweight mid

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That's exactly what I did. Purchased an RRA 16" middy with the chrome option and had it turned down to a lightweight profile by jtac:

http://www.jtacsupply.com/

If your looking for a "Dump a 20 round magazine into the side of the hill as fast as possible" gun, don't go lightweight

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My experience has been different. My lightweight's been to school and the barrel profile was not an issue even after many, many NSRs.

Get the superlight, and get it from either Colt or Bushmaster. You won't be sorry.


So many people underestimate the lightweight until they hold and shoot one, then they NEVER go back. Instant converts.


I don't know many people who've shot lightweights that still wanted to keep their HBARs. Very few. The only people that do that are highpower shooters or varmint shooters.


Lightweight was the original design, and Stoner got it right back then. The AR is not suppose to be a 12lb "carbine"...it's a light, handy, low recoil, fast shooting rifle.

Probably chrome-lined. If you maintain your weapon reasonably well, chrome lining is superfluous.

Mike

The rpoblem with your 4 desires' is that not too many people have the same desire. If you had to shuck one, I'd say go with an M4 profile barrel, it's the next lightest, and a lot easier to find.

Headless Thompson Gunner,

My 5 pound carbine has a standard forged lower with 4 pos collapsing stock at the moment. The upper is an A1 upper with no brass deflector, but a forward assist. You could probably find a slickside upper that will shave off a little more weight.

Good luck in your search!

The Armalite B15A4C barrel really isn't a HBAR (despite their description); you might find it perfectly suited to your needs.

I personally would go with a .750 "medium" barrel. It's not light, but not super heavy either. Around 2.5 pounds.. add the upper, and lower, handgaurd, light, and optic/mount - a little over 7 pounds.. Not "lightweight" but it works as an all around Carbine. Handy too.

Since the standard M1A is around 10.5 pounds with an optic, a "fully loaded" AR is significantly lighter.

Here is how I range AR15 carbines in weight

6 pounds and under - Too light
7 to 8 pounds - optimal
over 8 pounds - too heavy

but thats just me.