CMMG AR15 BARREL NUT

Description

The barrel nut is the unsung structural link between an AR-15 upper receiver and its handguard system, and replacing or having a spare on hand is straightforward insurance against a stripped or damaged original. CMMG’s mil-spec barrel nut for the AR-15 platform is built to the same dimensional standard used across the vast majority of AR-15 uppers, which means it fits without modification and accepts any mil-spec compatible handguard slip ring or delta ring assembly.

CMMG manufactures this nut from steel with a nitride finish. Steel is the conventional choice for barrel nuts because the nut must survive the torque applied during barrel installation — typically in excess of 30 foot-pounds — and maintain that clamping force over a service life that includes heating and cooling cycles from sustained fire. Nitride treatment hardens the surface and resists corrosion without adding meaningful thickness, so the finished part maintains the precise tolerances that mil-spec fitment requires.

This is a practical part for armorers, builders, and anyone refreshing a well-used upper. It pairs naturally with a new handguard slip ring or delta ring assembly if you are doing a full front-end rebuild. CMMG machines this to the same standards used in their own rifle production, so fitment against a standard AR-15 upper receiver extension should be straightforward.