
Availability: In Stock
Current Stock: Out of stock
The Faxon Firearms 5.56 NATO 10.5" barrel with pinned gas block combines a short, handy carbine setup with the added security of a factory-pinned gas block—no guesswork, no drift. Built for shooters who run short-barrel 5.56 builds (SBR, pistol, or firearm platforms) and want gas system reliability out of the box, this barrel arrives with the gas block already positioned and pinned to the barrel journal. You get the barrel, low-profile gas block, and roll pin included; just verify headspace and you're ready to finish your upper.
Faxon manufactures these barrels in-house from 4150 CMV steel, stress-relieved and button-rifled with a 1:8 twist rate—a versatile pitch that cycles everything from light practice rounds to heavier match ammunition. The 10.5" carbine profile keeps things lightweight and maneuverable, while the 1/2-28 muzzle threads accept standard suppressors and brakes. Both the bore and exterior are finished in Nitride, a proven hardening process that resists corrosion and wear without the brittleness of some alternative coatings.
Every barrel is individually headspace-checked with custom gauges and magnetic particle inspected for subsurface defects—the kind of quality-control steps that separate budget-tier barrels from ones you can actually trust in a short-barrel platform where gas system tuning is critical. The 11-degree target crown protects accuracy potential, and the pre-pinned gas block journal means you're not fighting a loose fit or relying solely on set screws to keep your gas block in place during strings of fire.
| Caliber | 5.56 NATO |
| Barrel Length | 10.5" |
| Twist Rate | 1:8 |
| Profile | Socom |
| Material | 4150 CMV |
| Rifling | Button rifled |
| Finish (Bore) | Nitride |
| Finish (Exterior) | Nitride |
| Muzzle Thread | 1/2-28 |
| Gas System | 10" Carbine |
| Gas Block Diameter | 0.750" |
| Gas Block Journal Length | 1.9" |
| Barrel Extension | M4 |
| Crown | 11-degree target |
| Weight | 1.10 lbs |
| Includes | Low-profile gas block, roll pin |
Yes. The 10.5" length and M4 extension work with standard AR platform uppers. Verify legality and NFA compliance for your build (SBR requires registration; pistol configurations depend on stock, buffer tube, and local law).
The 1:8 twist is a versatile all-around pitch. It stabilizes typical 55–77 grain 5.56 loads reliably, from budget practice ammo to heavier match or hunting rounds. It won't necessarily stabilize very light varmint rounds, but it's more forgiving than faster twists on the lighter end.
Yes. The low-profile gas block is pre-pinned to the barrel and included. It arrives hand-tightened to the barrel for shipping; you'll need to secure it properly (with set screws and the roll pin) during assembly and verify headspace before firing.
The roll pin runs through pre-drilled holes in the barrel journal and gas block, locking them together mechanically. Combined with set screws, this dual-retention method prevents the gas block from drifting or loosening during sustained fire—a real advantage in short-barrel or high-rate-of-fire builds where gas tube vibration can cause movement.

SKU: 167527005 • Weight: 1.5oz





Availability: In Stock
Current Stock: Out of stock
The Faxon Firearms 5.56 NATO 10.5" barrel with pinned gas block combines a short, handy carbine setup with the added security of a factory-pinned gas block—no guesswork, no drift. Built for shooters who run short-barrel 5.56 builds (SBR, pistol, or firearm platforms) and want gas system reliability out of the box, this barrel arrives with the gas block already positioned and pinned to the barrel journal. You get the barrel, low-profile gas block, and roll pin included; just verify headspace and you're ready to finish your upper.
Faxon manufactures these barrels in-house from 4150 CMV steel, stress-relieved and button-rifled with a 1:8 twist rate—a versatile pitch that cycles everything from light practice rounds to heavier match ammunition. The 10.5" carbine profile keeps things lightweight and maneuverable, while the 1/2-28 muzzle threads accept standard suppressors and brakes. Both the bore and exterior are finished in Nitride, a proven hardening process that resists corrosion and wear without the brittleness of some alternative coatings.
Every barrel is individually headspace-checked with custom gauges and magnetic particle inspected for subsurface defects—the kind of quality-control steps that separate budget-tier barrels from ones you can actually trust in a short-barrel platform where gas system tuning is critical. The 11-degree target crown protects accuracy potential, and the pre-pinned gas block journal means you're not fighting a loose fit or relying solely on set screws to keep your gas block in place during strings of fire.
| Caliber | 5.56 NATO |
| Barrel Length | 10.5" |
| Twist Rate | 1:8 |
| Profile | Socom |
| Material | 4150 CMV |
| Rifling | Button rifled |
| Finish (Bore) | Nitride |
| Finish (Exterior) | Nitride |
| Muzzle Thread | 1/2-28 |
| Gas System | 10" Carbine |
| Gas Block Diameter | 0.750" |
| Gas Block Journal Length | 1.9" |
| Barrel Extension | M4 |
| Crown | 11-degree target |
| Weight | 1.10 lbs |
| Includes | Low-profile gas block, roll pin |
Yes. The 10.5" length and M4 extension work with standard AR platform uppers. Verify legality and NFA compliance for your build (SBR requires registration; pistol configurations depend on stock, buffer tube, and local law).
The 1:8 twist is a versatile all-around pitch. It stabilizes typical 55–77 grain 5.56 loads reliably, from budget practice ammo to heavier match or hunting rounds. It won't necessarily stabilize very light varmint rounds, but it's more forgiving than faster twists on the lighter end.
Yes. The low-profile gas block is pre-pinned to the barrel and included. It arrives hand-tightened to the barrel for shipping; you'll need to secure it properly (with set screws and the roll pin) during assembly and verify headspace before firing.
The roll pin runs through pre-drilled holes in the barrel journal and gas block, locking them together mechanically. Combined with set screws, this dual-retention method prevents the gas block from drifting or loosening during sustained fire—a real advantage in short-barrel or high-rate-of-fire builds where gas tube vibration can cause movement.
SKU: 167527005 • Weight: 1.5oz
