Hornady Subsonic ammunition - designed for accuracy and performance below the speed of sound - now comes in both rifle and handgun loads. Subsonic Handgun utilizes tried-and-true XTP bullets that expand reliably at subsonic velocities. The Sub-X bullet used in Subsonic Rifle features a lead core. Long grooves in its gilding metal jacket combine with the bullet's flat profile and the patented Flex Tip insert within its hollow point cavity to help it expand reliably at low velocities. Powders are selected for optimal performance and consistency from lot to lot. Performance of 300 blackout subsonic meets or exceeds FBI protocol terminal ballistic test requirements, the XTP bullet in subsonic handgun has built a world-class reputation for accuracy and stopping power Silent and stealthy - Hornady Subsonic ammunition doesn't have the loud report of a supersonic round, and paired with a suppressor, it's even quieter Unique powders optimized for subsonic use result in a low flash signature, ideal for either suppressed or unsuppressed performance High quality components - with high quality cartridge cases and primers, subsonic ammunition offers the performance and accuracy shooters have come to expect from Hornady 4 inches test barrel length