Six silencers evaluated by PEW Science are included in this members-only Research Supplement to examine relative First Round Pop (FRP) and overall sound signature suppression performance characteristics. The silencers in this group were selected for their high flow rate characteristics and relatively high operator (shooter’s ear) Suppression Ratings on the untuned MK18 5.56x45mm NATO MK18 weapon system. The six silencers behave differently, even despite some of them exhibiting similar performance quantified by the PEW Science Suppression Rating. Their 5.56 MK18 suppression performance provides an excellent case study comparing current “low back pressure” rifle silencer technology

Typically, silencers possessing a high flow rate also possess lower sound suppression performance with subsonic ammunition and potentially lower bystander suppression performance, in general. However, there are significant exceptions. Hybrid designs have the potential to exhibit high performance in multiple regimes.

This research supplement is intended to provide more information to PEW Science members with regard to specific sound signature characteristics of the tested configurations in the aforementioned analytical test reports and to help frame objective loudness comparisons between six low back pressure 5.56 rifle silencers that use various technologies to suppress AR15 weapon signatures. Both FRP and total sound signature suppression regimes are examined. This supplement is part of ongoing PEW Science small arm weapon system sound signature research. PEW Science thanks you for your support.