The Stern Defense 6-inch .45 ACP barrel (brand part number 006-45ACP BARREL6INCH-D1-M) is a short, threaded barrel built for AR-15-pattern .45 ACP uppers. Made in the USA by STERN DEFENSE from 4150 chrome-moly steel with a Melonite coating, this barrel threads at .578-28 and carries a 1:16 twist rate matched to typical .45 ACP bullet weights. Because it measures only 6 inches, federal law restricts this barrel to a pistol-configured lower or a lower already registered as a short-barreled rifle; installing it on a shouldered-stock rifle lower without that registration would create an illegal, unregistered SBR. Sights are not included, and .45 ACP uppers built around this barrel require an enlarged ejection port along with an 11-ounce or heavier buffer when paired with a carbine-weight spring.

Key Specifications

• 6-inch barrel length.
• Rated for .45 ACP.
• .578-28 muzzle thread.
• 1:16 rifling twist rate.
• 4150 chrome-moly steel construction.
• Melonite coating for wear and corrosion resistance.
• No sights included.
• Requires an 11-ounce or heavier buffer when paired with a carbine-weight spring.
• .45 ACP uppers built around this barrel need an enlarged ejection port.
• Made in the USA.

Frequently Asked Questions

Do I need an ATF Form 4 to buy this barrel? No. A bare barrel by itself is not a regulated item; it only becomes a short-barreled rifle if installed on a shouldered-stock rifle lower. Install it only on a pistol-configured lower or a properly registered SBR receiver.

What buffer does this barrel require? An 11-ounce or heavier buffer when used with a carbine-weight spring.

Does this barrel come with sights? No, sights are not included.

Buy the Stern Defense 6-Inch .45 ACP AR-15 Barrel

Order this Stern Defense barrel from our Lubbock, Texas gun shop for quick, direct shipping as soon as it is ready to leave our shelf. Browse more gun parts and accessories from Schaefer Defense to finish your .45 ACP build.