he HRT-556 AM Silencer is a highly durable, low backpressure 5.56mm suppressor constructed from Griffin’s proprietary Nickel 625X powder alloy utilizing state-of-the-art DMLS additive manufacturing technology. This iteration of the HRT-556 Silencer shifts priorities to deliver an ultra low backpressure unit optimized for hard use while offering high levels of sound and flash reduction performance. Left handed shooters will benefit from the very low backpressure stack as well as right handed shooters. These silencers are built on Griffin’s rock-solid DUAL-LOK mounting system which has become one of the most trusted active-locking mounting systems preferred by law enforcement and military professionals. This advanced mount provides exceptional accuracy with minimal and repeatable POI shift, and completely eliminates the fear of unintended loosening during prolonged courses of fire. The proprietary, patent-pending Nickel 625X alloy showed in testing a ~68% increase in yield and tensile strength over additively manufactured INCONEL 625 at 1200°F. INCONEL 625 is a commonly used suppressor alloy in current next generation military suppressors. Additively manufactured Nickel 625X is stronger at 1472°F than INCONEL 625 cold formed sheet material at room temperature. INCONEL 625 cold formed material provided adequate service in the last several decades of military suppressors.