The Dead Air KeyMo Muzzle Brake M18-1.5 AI is a full-size muzzle brake from Dead Air Silencers (brand part no. DA106), threaded M18-1.5 AI for .338 caliber barrels. It is built as the interface for the KeyMo suppressor mounting system, pairing multi-port recoil reduction with a precision taper that returns to zero on every mount. The body is 4140 heat-treated alloy steel with a Black Nitride finish. It targets long-range rifles chambered in .338 caliber that carry the M18-1.5 AI muzzle thread.

Key Specifications

• The muzzle thread is M18-1.5 AI, the pitch that decides which barrels this version fits.
• The through bore is sized for .338 caliber barrels, matching the thread pitch it is paired with.
• Material is 4140 heat-treated alloy steel, which suits a brake that sees hard recoil loads.
• The finish is Black Nitride, which adds corrosion and wear resistance.
• Overall length is 2.82 inches, enough room for a multi-port brake body.
• Weight is 4.10 ounces, a modest load on the end of the barrel.
• It is a multi-port design that keeps the rifle flat under recoil and fast on follow-up shots.
• The mount uses a taper interface with a mechanical detent, which resists loosening under heat and vibration.
• A shim kit with instructions is included for timing the brake on the barrel.
• This version has no pin and weld hole and no port holes on the top wrench flat, unlike the 1/2-28 and 5/8-24 versions.

Frequently Asked Questions

Does it work without a suppressor? Yes. It is a full-size muzzle brake that cuts recoil on its own, and it is also the purpose-built interface for the KeyMo suppressor mounting system.

What thread and bore does this version have? It is threaded M18-1.5 AI with a .338 caliber bore. Dead Air sells the KeyMo Muzzle Brake in several thread pitches, so match it to your muzzle thread.

Does it need shims to be timed? Yes. KeyMo brakes come with an included shim kit and instructions for timing the muzzle device on your barrel.

Buy the Dead Air KeyMo Muzzle Brake M18-1.5 AI, .338 Cal

The M18-1.5 AI thread is the pitch Dead Air lists for Accuracy International rifles, and this brake brings the KeyMo interface to it. Order it from our Lubbock, Texas gun shop for fast direct shipping, and browse more Class 3 parts and accessories while you are here.