FAXON MATCH SERIES PENCIL PROFILE 16" MID-LENGTH 223 WYLDE AR15 BARREL

Rifle Barrels › Match Series › 223 Wylde › 16″ Pencil, 1:8, Mid-Length  |  Works with: .625″ gas block • mid gas tube • Gunner Lightweight BCG • 1/2x28 muzzle devices • 5.56 suppressors

Why 223 Wylde

223 Wylde is a chamber, not a different cartridge. Gunsmith Bill Wylde designed it to split the difference between the .223 Remington and 5.56 NATO chambers: it keeps the long freebore and gentle leade angle of the NATO chamber, so 5.56 pressures stay safe, and pairs them with the tighter .224″ freebore diameter of the .223 Rem, which helps accuracy.

The result is one barrel that shoots both 5.56 NATO and .223 Remington safely and shoots the heavier match bullets precision shooters want. That is why it is the chamber Faxon uses across its Match Series 5.56-class barrels.

Go deeper: Definitive Guide to 223 Wylde • 5.56 NATO vs 223 Wylde • 5.56 Barrel Guide • All 223 Wylde barrels

Why a 1:8 Twist

A 1:8 twist handles the full range of common AR-15 bullets, from 55 gr FMJ to the 77 gr match bullets that 223 Wylde shooters buy it for. Sierra rates its 77 gr MatchKing for 1:8 or faster. The 80 to 80.5 gr long-range bullets sit at the edge of what a 1:8 stabilizes, and they are usually single-fed because they run past magazine length.

Velocity by Barrel Length

Published chronograph data from separate test rifles, so treat these as ranges, not exact figures.

Sources: Lucky Gunner Lounge (14.5/16/18″), RifleShooter.com cut-down test (18/20″), and TFB (77 gr TMK). Estimates, not Faxon testing.

The Pencil Profile and Mid-Length Gas

The Pencil profile is Faxon’s lightest contour. It heats up quickly but also cools quickly, and because every Faxon Match 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. Mid-length gas moves the port farther from the chamber than carbine gas, for a softer, smoother impulse and less wear on the bolt.

What “Match Series” Means

Match Series is Faxon’s 416-R stainless line. 416-R machines cleanly and holds a consistent bore, and Faxon button rifles it with 5R rifling, five lands with sloped sides instead of sharp-cornered ones, which deforms the bullet less and fouls less. Then the barrel is salt-bath QPQ nitrided inside and out. Nitride is a diffusion treatment, not a plating: it hardens the bore surface and adds corrosion resistance while adding virtually nothing to the dimensions, a few ten-thousandths of an inch, roughly a tenth the width of a human hair. It needs little to no break-in.

How it compares to Faxon’s other lines: the Duty Series is 4150 CMV with the same nitride finish, the hard-use option; the MATCH-X Series takes 416-R further with a honed and lapped bore and an uncoated exterior; and the Combat Series offers classic configurations with chrome-lined bores and manganese phosphate.

What’s in the Box

How It’s Made

1. Drill and ream: The 416-R bar is gun-drilled and pull-reamed.
2. Button rifle: 5R button rifled, right-hand 1:8 twist.
3. Air gauge: Bore air gauged.
4. Stress relieve: Stress relieved at the blank stage, then qualified true to the bore.
5. Profile, thread, crown: Pencil profile turned, .625″ journal held concentric to the bore, 1/2x28 threads cut, target crown.
6. Chamber: 223 Wylde chamber cut and CMM-checked.
7. MPI and nitride: Wet magnetic particle inspected, then salt-bath QPQ nitrided inside and out.
8. Port and extension: .081″ gas port drilled and reamed; NP3 extension torqued to 150 ft-lb, pinned, and 100% headspaced.
9. Mark and inspect: Laser-marked “.223 WYLDE 1-8T 5R 416R MPI”, then final inspection of the crown, feed ramps, chamber, and threads.

How We Inspect It

Faxon barrels are built to a written control plan, and each run is logged on inspection sheets. Here is what this barrel goes through before it ships.

What Reviewers and Owners Say

Average ratings, out of 5 stars: 5.0 on FaxonFirearms.com; 4.9 at OpticsPlanet (223 Wylde Pencil listing); 5.0 at Brownells (223 Wylde Pencil listing).

Build It Out: Faxon Parts That Fit This Barrel

Compare Faxon Match Series 223 Wylde Barrels

Match Series 16″ 223 Wylde FAQs

Can I shoot 5.56 NATO in a 223 Wylde barrel?

Yes. The 223 Wylde chamber keeps the long freebore and leade of the 5.56 NATO chamber, so 5.56 pressures stay safe, while its tighter freebore diameter helps .223 Remington and match ammunition shoot accurately.

Will a 1:8 twist stabilize 77 gr bullets?

Yes. A 1:8 stabilizes 55 to 77 gr bullets, and Sierra rates its 77 gr MatchKing for 1:8 or faster. The 80 to 80.5 gr long-range bullets are marginal in a 1:8 and are usually single-fed.

What bolt and magazines does it use?

A standard 5.56 bolt and bolt carrier group, and standard 5.56/.223 AR-15 magazines.

What gas block and gas tube does it take?

A .625″ gas block on the 1.1″ journal and a mid-length gas tube. Faxon’s patented adjustable .625″ block is the recommended pick, especially suppressed. The gas port is .081″, reamed to size.

Will it run suppressed and unsuppressed?

Yes. A suppressor adds back-pressure, so Faxon recommends its patented adjustable gas block: tune it for your can and ammunition, then open it back up when you shoot unsuppressed. If you run a lightweight carrier, always pair it with an adjustable gas block.

How is Match Series different from Duty Series and MATCH-X?

Match Series is 416-R stainless with 5R rifling and QPQ nitride inside and out. Duty Series is 4150 CMV with the same nitride finish. MATCH-X is 416-R with a honed and lapped bore and an uncoated exterior. All are made in Greater Cincinnati.

Is the nitride inside the bore?

Yes. Salt-bath QPQ nitride is a diffusion treatment, not a plating, so it hardens the bore and exterior while adding virtually nothing to them: the surface grows by a few ten-thousandths of an inch, roughly a tenth the width of a human hair. It needs little to no break-in.

Does it come with a gas block, gas tube, or muzzle device?

No. It ships with the nickel-Teflon extension installed, torqued to 150 ft-lb, pinned, and headspaced. Gas block, gas tube, and muzzle device are sold separately; the muzzle is threaded 1/2x28.

Is it full-auto capable, and how much heat can it take?

Yes. Like every Faxon nitrided rifle barrel, it is full-auto capable. The barrel is stress relieved, magnetic particle inspected for flaws, and salt-bath nitrided at roughly 1,050°F, so the steel and the nitride are stable far beyond normal firing temperatures. 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. Light profiles like the Pencil heat up faster than heavier contours, so expect to reach those limits sooner. Push past that and throat wear speeds up, which shortens barrel life. If the barrel smokes or starts to glow, stop: near 1,000°F the steel is approaching the temperature it was nitrided at, where it can begin to soften and the nitride can lose hardness, and military testing has seen M4 barrels fail at about 1,360°F. A hot chamber can cook off a round in as little as 10 seconds, so clear it quickly or keep it pointed in a safe direction. And heat affects accuracy in every barrel: groups open up as it heats. Faxon’s stress relieving and machining keep point of impact from walking, but let it cool before you check zero or shoot for groups.

Where is it made, and what is the warranty?

Made in Greater Cincinnati, Ohio, and 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. Velocity, stability, and energy figures come from published ammunition-maker and independent test data, not Faxon testing; results vary with ammunition, barrel, and conditions. MuzzLok®, HARMONIX®, CORESYNC®, and Flame Fluted® are trademarks of Faxon Firearms. Know and follow all federal, state, and local laws.