The One Horse 10.5in 5.56 NATO Carbine-Gas AR15 Barrel (part no. OHBR05) is a bare replacement or build barrel chambered in 5.56 NATO with a carbine-length gas system sized for its short length. One Horse cuts this barrel with a 1:7 twist rate, fast enough to stabilize heavier 5.56 projectiles for pistol- and SBR-length builds.

Key Specifications

• Chambered in 5.56 NATO, also safe to run standard .223 Remington ammunition.
• Cut to 10.5 inches, a common length for short-barreled pistol and registered SBR builds.
• Paired with a carbine-length gas system, matched to this barrel’s short length for reliable cycling.
• Rifled at a 1:7 twist rate, fast enough to stabilize heavier 5.56 bullet weights.
• Ships at approximately 1.3 lb, typical for a barrel of this length.

Frequently Asked Questions

What gas system does this barrel use? A carbine-length gas system, sized to this barrel’s 10.5-inch length.

What twist rate is this barrel? 1:7, which stabilizes a wide range of 5.56 bullet weights including heavier match loads.

Is a barrel this short legal to buy? Yes. A bare barrel, or a complete upper with no lower attached, is not itself a regulated firearm under the NFA. It only becomes a regulated Short-Barreled Rifle if it’s built onto a rifle-configured lower with a shoulder stock at an overall barrel length under 16 inches without prior ATF approval; pairing it with a pistol lower/brace setup or an already-registered SBR avoids that issue.

Buy the One Horse 10.5in 5.56 NATO Carbine-Gas AR15 Barrel

Order this 10.5-inch 5.56 barrel from One Horse. Ships fast from a Lubbock, TX gun shop. See our full AR15 barrels selection for more build options.