Expo Arms Combat Series 11.5" 5.56 NATO Chrome Lined AR-15 Barrel - SOCOM Profile - Carbine Length

Manufactured by Expo Arms
SKU: XP-B-556-115-SOC-C
MPN: XP-B-556-115-SOC-C
Manufactured by Expo Arms
19 Reviews

In Stock

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The Expo Arms Combat Series AR-15 Barrels are designed to give you a premium barrel at an affordable cost. This AR barrel is made from Mil-Spec 11595E certified 4150 steel and features a chrome lined bore to withstand high temperatures for a long barrel life. This 11.5” model features a SOCOM profile with a carbine gas system and .070” port diameter for reliable function. Additionally, the .750 gas seat diameter is dimpled for securely attaching set screw gas blocks. The 1:7 twist rate is optimal for heavier 62 grain ammunition and the muzzle is threaded 1/2x28 for your favorite 5.56 muzzle device. The entire 5.56 Barrel is Phosphate coated for corrosion resistance and oil absorption. If you are looking for a combat ready barrel that provides exceptional accuracy and reliability, you can’t go wrong with an Expo Arms M4 barrel.

  • 11.5” SOCOM profile chambered in 5.56 NATO
  • Carbine gas system with .070” port diameter
  • .750” dimpled gas block shelf
  • Made from Mil-Spec 11595E 4150 steel
  • Chrome lined bore with Phosphate outer finish
  • 1:7 twist rate and 1/2x28 muzzle thread
  • M4 feed ramps

Expo Arms offers top-quality MIL-SPEC AR-15 components at rock bottom prices. Made in the U.S.A. and covered by Expo’s Limited Lifetime Warranty against manufacturer defects, material or workmanship problems, and even normal wear and tear.
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Barrel CoatingManganese Phosphate
Barrel ContourSOCOM
Barrel Length11.5
Barrel LiningChrome
BrandExpo Arms
Caliber Gauge5.56 NATO
Gas Seat Diameter.750
Gas System LengthCarbine
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.

Ratings & Reviews

19 reviews

  • 3 stars
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looks great

by -

If it shoots 1/2 as good as it looks, I'll be VERY happy.
<br>A no brainer for under a C note.

Going to order another

by -

Dimpled gas for gas block, nice quality phosphate finnish. Accurate

Looks good

by -

I bought the wrong length barrel for my suppressor to clear my handguard so this is just on a shelf in its tube still. I'll use it someday on another build, Looks nice though.

11.5” Chrome Lined Barrel


This is my third ExpoArms barrel. I also have their 14.5” and 10.3”. These barrels are the shits! I’m actually going to build another 14.5” RECCE rifle. You can’t go wrong with these barrels. Now if only they can make some 12.5”… I’ll be all over them in a heartbeat. Thank you PA—- Semperfi

Excellent Barrel

by -

I wanted to go to a 11.5 barrel for a tad more dwell on my AR pistol. The fact that the profile is heavier and it's chrome lined was a big selling point. After installation it proved very accurate, and I have had no feeding problems at all. Lets just say for the price I am very pleased- VERY! So, I ordered another for an additional build! If your looking for a great 11.5 barrel at a reasonable price that performs- this is a great choice. Note: the specs says it's dimpled for installation of a set screw gas block. Neither of mine were. However, with the money you are saving you can purchase a dimpling jig and accomplish the job in about 10 minutes.

great barrel

by -

Made a XM177 with it shoot grea And accurate

Good Barrel, Good Value

by -

I paired this barrel with the forged Expo Arms upper receiver and upper parts kit for my most recent build. Barrel broke in just fine and was holding good groups at 50 meters with a red dot optic after the first 50 rounds. I did do a hasty bore sight to align the dot with the bore before I began shooting and shot 50 rounds before I began making adjustments to the optic to make sure that the barrel was good to go. I fired around 150 rounds through the barrel on that day and 50 of those were suppressed and no issues at all. I would use this barrel again for another build.

Great Barrel Great Price


Gave this barrel a try and I have to tell you how shocked I was when it arrived just how nice this barrel is! Went together so smooth and runs everything with zero malfunctions, with my hand loads I was able to achieve .5 moa …. Again shocked….. Ive never really looked at Expo but they have my attention so hand guard and BCG next….. Thank you EXPO and thank you Primary Arms for fast shipping and GREAT products they carry.

Excellent barrel


Can’t beat it for the price in my opinion. Especially if you catch it on sale. Chrome lined, heavy duty, excellent consistent groupings. Will definitely purchase another expo barrel in the future