FAXON ION SERIES 16" THREADED PENCIL 5.56 BARRELED UPPER
FaxonFAXON ION SERIES 16" THREADED PENCIL 5.56 BARRELED UPPER
Ultra-lightweight performance for AR-15 builds — 16" pencil profile barrel threaded for custom muzzle devices, mid-length gas tuned with patented adjustable block, 1:8 twist, black nitride finish, Streamline Carbon Fiber 15" M-LOK handguard, MuzzLok® Plan B flash hider for suppressor-ready timing — engineered for speed, balance, and reliability in Greater Cincinnati, Ohio.
What it is
The Faxon ION Series 16" Threaded Pencil 5.56 Barreled Upper is an ultra-light, suppressor-ready upper assembly designed for shooters prioritizing minimal weight with maximum versatility and control. The pencil profile minimizes mass for fast transitions and easy carry, while the threaded muzzle (1/2x28) comes with Faxon’s MuzzLok® Plan B flash hider for effective flash hiding, repeatable timing (no shims), and direct HUB-mount suppressor compatibility — ideal for competition, training, defensive setups, or lightweight hunting builds.
Core is Faxon’s Duty Series 4150 CMV barrel (button-rifled in-house, 1:8 twist, stress-relieved, MPI-inspected, black nitride finish) with mid-length gas system for smooth cycling. Features Faxon’s patented adjustable .625" low-profile gas block for precise tuning (suppressed/unsuppressed or ammo-specific), and the Streamline Carbon Fiber 15" M-LOK handguard for extreme weight savings and modular mounting. Mid-length stainless gas tube completes the lightweight package.
Built for those who want a rifle that moves as quickly as they do — lightweight, balanced, and suppressor-optimized.
Who it’s for / not for
- Best for: Lightweight suppressed builds, competition, high-round-count training, defensive rifles, hunters or hikers prioritizing speed and low weight over heavy thermal mass.
- Good match: Mil-spec AR-15 lowers, red-dot/magnified optics, HUB/Plan B suppressors, setups needing tunable gas for suppressors or ammo variations.
- Not ideal for: Sustained full-auto or extreme high-heat/full-auto use (consider SOCOM profile), benchrest precision where maximum rigidity is key.
Key features
- 16" Pencil Profile Barrel (Threaded) — ultra-light design with 1/2x28 threads for custom muzzle devices
- Duty Series 4150 CMV • Black Nitride — durable, corrosion-resistant, easy cleaning
- 1:8 Twist Rate — stabilizes popular 55–77 gr 5.56 loads
- Mid-Length Gas System — smoother recoil impulse, improved reliability
- Patented Adjustable .625" Gas Block — tunable for suppressed/unsuppressed use or ammo variations
- MuzzLok® Plan B Flash Hider — flash reduction + HUB suppressor compatibility with repeatable, shim-free timing
- Streamline Carbon Fiber 15" M-LOK Handguard — extreme weight reduction, strong, modular mounting
- Made in Greater Cincinnati, Ohio — 100% Faxon Firearms manufactured & assembled
Related shopping shortcuts
Backed by Faxon Firearms’ Limited Lifetime Warranty.
Full terms & exclusions: https://faxonfirearms.com/warranty-privacy-terms/
Bill of Materials (exact components used)
Use these links to verify compatibility, plan upgrades, or source spare parts.
Quick specs summary: Suppressor-ready 16" 5.56 NATO ION Series Threaded Pencil barreled upper — 4150 CMV black nitride pencil barrel (1:8 twist, mid-length gas, .625" journal), MuzzLok® Plan B flash hider (1/2x28, .250" bore), patented adjustable gas block, Streamline Carbon Fiber 15" M-LOK handguard. Ultra-lightweight, suppressor-optimized for speed and precision. Made by Faxon Firearms in Greater Cincinnati, Ohio.
FAQs
Is this compatible with standard AR-15 lower receivers?▾
Yes. This 5.56 barreled upper mates directly with standard mil-spec AR-15 lower receivers.
Is this upper suppressor ready?▾
Yes — highly optimized for suppression. Ships with Faxon MuzzLok® Plan B flash hider (1/2x28, .250" bore) for direct HUB-mount suppressor compatibility. The patented adjustable gas block allows precise tuning for suppressed shooting. Timing nut ensures repeatable POI with minimal shift.
Where is the barrel made?▾
Made in the USA — Faxon manufactures the Duty Series barrel in-house in Greater Cincinnati, Ohio.
What is “ION Series” and why choose it?▾
ION Series focuses on ultra-lightweight components with premium materials (carbon fiber handguard) for speed and balance without sacrificing reliability — ideal for competition, training, or defensive builds where weight matters.
What’s the advantage of the pencil profile?▾
The slim pencil contour minimizes weight for fast handling and easy carry, while still providing good harmonics and velocity — great for lightweight setups where every ounce counts.
Does this include a bolt carrier group or charging handle?▾
No — this is a barreled upper assembly only. Pair it with a BCG from the "Shop BCGs" link above to complete your build.
What warranty backs this upper?▾
All Faxon Firearms products include our Limited Lifetime Warranty. Full terms, service, and exclusions at:
https://faxonfirearms.com/warranty-privacy-terms/
- Caliber:
- 5.56 NATO