Cmmg Ar15 9.2'' 22Lr Barrel W/ Collar

The CMMG AR15 9.2" .22 LR barrel with collar is a dedicated rimfire barrel built to solve a real problem: accuracy loss when firing .22 LR ammunition through a centerfire .223/5.56 barrel. This 9.2-inch barrel is designed to work with Atchison-style .22 LR conversion kits—including CMMG and Ciener units—letting you transform your AR upper into a dedicated .22 LR shooter without the ballistic compromise of oversized bores. If you run a .22 conversion kit and want precision and reliability, this barrel delivers it.

Installation is straightforward on any mil-spec upper receiver using a standard or free-float barrel nut. The barrel ships with a pre-installed extension and locator pin, plus a chamber adapter specific to this barrel. One critical step: you'll need to swap out the conversion kit's original .223/5.56-to-.22 LR adapter and replace it with the one included here—just take care not to spring the conversion unit's rails during removal. Once installed, the barrel's standard 1/2" x 28 threads accept any AR-pattern muzzle device, so you can add a suppressor, brake, or flash hider as your mission demands.

Built for shooters who want to run .22 LR conversions seriously—whether that's plinking, training, or precision rimfire work—this CMMG barrel ensures your conversion kit performs to spec. The dedicated bore eliminates the accuracy issues that plague larger-diameter centerfire barrels firing small-bore ammo, giving you the accuracy and consistency you'd expect from a dedicated .22 rifle. It's a smart upgrade for anyone running a quality conversion unit.

Key Features

• 9.2-inch M4-contour barrel optimized for .22 LR ammunition
• Dedicated rimfire bore eliminates accuracy loss from oversized centerfire barrels
• Works with Atchison-style conversion kits (CMMG, Ciener, and compatible units)
• Pre-installed barrel extension with locator pin for proper alignment
• Includes chamber adapter; requires swapping conversion kit's original adapter
• Installs on mil-spec upper receivers with standard or free-float barrel nut
• 1/2" x 28 TPI muzzle threads for AR-pattern brakes, suppressors, and flash hiders

Specifications

Frequently Asked Questions

What conversion kits does this barrel work with?

This barrel is designed for Atchison-style .22 LR conversion kits, including CMMG and Ciener units. You'll need a compatible conversion kit (sold separately) and a rimfire magazine—CMMG or Black Dog brands are recommended—to complete the .22 LR conversion.

Do I need any special tools or parts to install this barrel?

You'll need a standard or free-float barrel nut compatible with your upper receiver. The barrel comes with a chamber adapter that replaces the conversion kit's original .223/5.56-to-.22 LR adapter. Installation requires careful removal of that original adapter to avoid springing the conversion unit's rails.

Can I use my existing AR upper receiver?

Yes, this barrel installs on any mil-spec upper receiver. It works with both standard and free-float barrel nut setups, so you don't need a special upper—just your existing AR-15 upper as the base for your .22 LR conversion.

What muzzle devices can I attach?

The barrel has standard 1/2" x 28 TPI muzzle threads, so you can use any AR-15 or M16-pattern muzzle component—brakes, flash hiders, suppressors, or other devices designed for that thread pitch.