FAXON Firearms AR-15/M16 14.5 Pencil Barrel 4150 QPQ Mid .625
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Faxon Firearms
Overview
The Faxon Firearms AR-15/M16 14.5 Pencil Barrel is designed for builders looking to optimize their lightweight setups without sacrificing performance. This barrel features a mid-length gas system, which helps to reduce recoil and improve cycling, paired with a 1:8 twist rate that stabilizes a wide range of 5.56 NATO ammunition. Its .625 gas block diameter allows for compatibility with slim profile gas blocks, making it a popular choice for builds seeking a balance of weight and functionality.
Specifications
FAXON Firearms AR-15/M16 14.5 Pencil Barrel 4150 QPQ Mid .625
Available Merchants(6)
Prices checked
Price Alert
October 2026 on GunPartPicker
FAXON Firearms AR-15/M16 14.5 Pencil Barrel 4150 QPQ Mid .625 ranked #131 of the 329 barrels builders added on GunPartPicker in October 2026. Builders have added it to their builds on GunPartPicker. Since April 2026, it ranks #201 of the 1,047 barrels builders have added. Builds with this barrel are nearly all chambered in 5.56 NATO, nearly all on mid-length gas, and nearly all AR-15.
Availability is good: it was in stock at one retailer or another nearly every time we checked in October 2026, and today all 6 retailers we track have it in stock. Buying today, the lowest price is $141.68 at AT3 Tactical, which matches the best price we saw in October.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
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Read the guide: AR-15 Barrel Length & Brand Report →Check it against the live catalog:
Frequently Built With
The part most often added in each category by the builds that include this one
Zro Delta AR-15 Forged M4 Stripped Upper Receiver
Guntec USA AR-15 Ambidextrous Quick Engage Charging Handle Anodized Bronze
BLEM PSA AR-15 Lower Safe/Fire
WMD Guns M16 NIB-X® Bolt Carrier Group W/ Hammer
FAXON Streamline Carbon Fiber M-LOK AR-15 Handguard - 13"
Zro Delta AR-15 Fire Control Group Laser Cut Disconnector
Builds Featuring This Part
See all builds →Builds in the community that include the Faxon Firearms Ar-15/m16 14.5 Pencil Barrel 4150 Qpq Mid .625
| Build | Parts | Total |
|---|---|---|
 | 6 | $897.61 |
 | 14 | $760.50 |
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