Integral vs. Pin and Weld
Federal law requires a rifle barrel to be at least 16″ long. The common workaround is a 14.5″ barrel with a muzzle device pinned and welded on to reach 16″. It works, but it is permanent, the weld is only as good as the shop that did it, and the device often traps the barrel nut and handguard behind it.
Faxon’s Integral® Series takes a different route. The brake or flash hider is machined from the same 4150 CMV barrel blank, on the same axis as the bore, so the barrel measures 16″ overall with nothing pinned or welded. The device is perfectly concentric with the bore, and because there is no weld holding anything in place, the barrel nut, gas block, and handguard can still come off when you change the build.
| Integral® Series | 14.5″ pinned and welded |
|---|
| Overall length | 16″, device machined in | 16″ with device pinned and welded |
| Device alignment | Concentric with the bore, cut on the same axis | Depends on threads and the weld |
| Barrel nut and handguard | Can still come off | Often trapped behind the device |
| Change the device later | No | No, without cutting the weld |
| Suppressor host | No | Only with a compatible permanent device |
Brake or Flash Hider?
Integral 3-Port Brake (5.56) and Integral 2-Port Brake (9mm). Ports redirect gas to cut muzzle rise and felt recoil, so the rifle stays flatter for fast follow-up shots. Expect more concussion and noise to the sides.
Integral A2-Style Flash Hider (5.56) and Integral Slim Flash Hider (9mm). Reduce visible flash, especially in low light, and are easier on shooters beside you.
California: the flash hider versions cannot be shipped to California.
Compare the Integral® Barrels
| Barrel | Caliber | Integral device | Gas | Weight | MSRP |
|---|
| 16″ Gunner | 5.56 NATO | 3-Port Brake | Mid, .625″ journal (1.9″ long) | 1.35 lb | $261 |
| 16″ Gunner | 5.56 NATO | A2-Style Flash Hider | Mid, .625″ journal (1.9″ long) | 1.35 lb | $261 |
| 16″ Pencil | 5.56 NATO | 3-Port Brake | Mid, .625″ journal (1.1″ long) | 1.20 lb | $262 |
| 16″ Pencil | 5.56 NATO | A2-Style Flash Hider | Mid, .625″ journal (1.1″ long) | 1.19 lb | $262 |
| 16″ Light Taper | 9mm | 2-Port Brake | Blowback (no gas port) | 1.34 lb | $222 |
| 16″ Light Taper | 9mm | Slim Flash Hider | Blowback (no gas port) | 1.34 lb | $222 |
5.56 NATO or 9mm?
5.56 NATO (Gunner or Pencil). 1:8 twist, mid-length gas on a .625″ journal (1.9″ long on the Gunner, 1.1″ on the Pencil). Use a .625″ low-profile block, Faxon’s adjustable or fixed, with a mid-length gas tube. Faxon’s Gunner profile puts steel where a barrel needs stiffness, at the chamber and under the handguard, and trims it out front. You get Government-profile durability with close to Pencil-profile handling, which is why it is Faxon’s most popular contour.
Pencil durability. The Pencil profile is Faxon’s lightest contour. It heats up quickly but also cools quickly, and because every Duty Series barrel is stress relieved and 100% wet magnetic particle inspected, it is a surprisingly rugged barrel that punches above its weight. It is not a benchrest profile, and it is not meant to be.
9mm (Light Taper). A straight blowback barrel with no gas port, 1:10 twist, with feed ramps finished for both Glock®-pattern and Colt-pattern magazines. Pair it with a 9mm blowback bolt carrier, a matched buffer and spring, and a lower, bolt, and ejector set up for your magazine pattern.
Fitment
Any mil-spec AR-15 upper set up for the caliber works; the Faxon Enhanced Forged Upper is a good match. Because the device is part of the barrel, the handguard has to stop behind it: a free-float handguard of 13″ or shorter, like the Faxon Streamline 13″, clears the integral device. The muzzle is not threaded and the device cannot be removed.
How Every Integral® Barrel Is Made
- Drill and ream: 4150 CMV bar gun-drilled and reamed
- Button rifle: Button rifled, 1:8 twist for 5.56, 1:10 for 9mm
- Air gauge: Bore air gauged
- Stress relieve: Stress relieved at the blank stage, then qualified true to the bore
- Profile and device: Profile turned and the brake or flash hider machined from the same blank, on the same axis as the bore
- Chamber: 5.56 NATO or 9mm chamber cut
- MPI and nitride: 100% wet magnetic particle inspected, then salt-bath QPQ nitrided inside and out
- Finish: 5.56: gas port drilled and M4 extension torqued, pinned, and headspaced. 9mm: feed ramps finished for Glock®- and Colt-pattern magazines
- Inspect: Laser-marked and final inspected
What Owners Say
Integral® barrels average 4.8 out of 5 stars across 13 reviews on FaxonFirearms.com. Owners call out the fit and finish, the accuracy of the 9mm, and how much simpler a 16″ build is without a pin and weld.
“Haven't got it installed yet but I'm impressed by the design and workmanship. Gives a nice compact package and some weight savings.”
David, verified buyer • 16″ Gunner
“This barrel is fantastic! It shoots sub MOA and everyone I let use the rifle was amazed that they could ring 4" steel disks at 150 yards.”
Julio, verified buyer • 16″ Light Taper
“If you are wanting to stick with a 16” barrel and note go the 9mm pistol or SBR route, the integral flash hider and compensated 9mm barrels are awesome options! As usual for Faxon, great fit, finish, and accuracy!”
Mark Bellanger, verified buyer • 16″ Light Taper
Faxon AR-15 and AR-10 barrels have been voted Favorite Aftermarket Barrel by Shooting Sports Retailer every year since 2022, the Gold Award.
Integral® Series FAQs
Is an Integral barrel legal for a rifle build?
Yes. The device is machined into the barrel, so it measures 16″ overall with no pin and weld, meeting the federal 16″ minimum for a rifle barrel. Know and follow your state and local laws too.
Can I remove or change the muzzle device?
No. The device is part of the barrel blank and there are no muzzle threads. Choose the brake or flash hider version that fits how you shoot.
Will it work with a suppressor?
No. The barrel isn’t threaded and the device can’t be removed, so it isn’t a suppressor host. If you plan to shoot suppressed, choose a threaded Duty Series barrel.
Why not just pin and weld a 14.5-inch barrel?
A pinned and welded device is permanent and often traps the barrel nut and handguard behind it. With an Integral barrel there is nothing to pin or weld, the device is concentric with the bore, and the barrel nut, gas block, and handguard can still come off.
Can the flash hider versions ship to California?
No. The integral flash hider versions cannot be shipped to California.
What handguard fits?
A free-float handguard of 13″ or shorter, so it stops behind the integral device. The Faxon Streamline 13″ is a direct fit.
What gas block and tube do the 5.56 barrels take?
A .625″ low-profile gas block and a mid-length gas tube. The journal is 1.9″ long on the Gunner and 1.1″ on the Pencil. Faxon’s fixed and adjustable .625″ blocks both fit.
Does the 9mm barrel need a gas block?
No. It is a straight blowback barrel with no gas port. Use a 9mm blowback bolt carrier with a buffer and spring matched to it. The feed ramps work with Glock®-pattern and Colt-pattern magazines.
What does 4150 CMV and nitride mean?
4150 CMV is a chrome-moly-vanadium barrel steel known for toughness and wear resistance. Salt-bath QPQ nitride is a diffusion treatment, not a plating: it hardens the bore and exterior and adds corrosion resistance while adding virtually nothing to the dimensions, and it needs little to no break-in.
Are these barrels full-auto capable?
Yes. Like every Faxon nitrided rifle barrel, they are full-auto capable. What limits any barrel on automatic fire is heat. A good guideline, drawn from U.S. military guidance for the M4 carbine: about 12 to 15 rounds a minute can be fired indefinitely, and continuous rapid fire should stop at about 150 rounds so the barrel can cool. Short and light barrels heat up faster, so expect to reach those limits sooner. If a barrel smokes or starts to glow, stop. Groups open up as any barrel heats; Faxon’s stress relieving keeps point of impact from walking, but let it cool before you check zero. Each product page has the full heat guidance.
Where are they made?
In Greater Cincinnati, Ohio, and every barrel is covered by the Faxon Lifetime Guarantee.
Full-auto heat guidance is general, based on published U.S. military rate-of-fire guidance and steel and nitride data, not Faxon testing; barrel life under automatic fire depends on rate of fire, ammunition, and cooling. Glock® is a registered trademark of Glock, Inc.; Faxon is not affiliated with Glock. MuzzLok® and HARMONIX® are trademarks of Faxon Firearms. Know and follow all federal, state, and local laws.
