This is a factory Surefire tool designed to remove carbon build-up from 5.56 muzzle devices: flash hiders, brakes and Surefire Warcomp as well. The ACST may not make your muzzle device fully shin, but properly used, it will remove enough carbon to assure a proper fit to a Surefire suppressor.
The SureFire Adapter Carbon Scraping Tool (ACST) is designed to remove carbon fouling from the corresponding SureFire suppressor adapter to an adequate level for proper suppressor attachment. While carbon may still be visible on the adapter, this is not a concern as the ACST is designed to ensure that correct tolerances are kept for precise suppressor fitment. The ACST is compatible with most SureFire muzzle brakes, flash hiders and WARCOMPS. Simply place the ACST over the SureFire “Suppressor Adapter” and rotate clockwise and counter-clockwise until carbon fouling is removed. The ACST requires little maintenance and can either be wiped or blown with compressed air to clean the inside of the tool. Stainless steel construction and a nitride prevent corrosion. Cut your field cleaning time with a SureFire ACST.