450 Bushmaster Tbd Gr Sub-x® (20pk)Shhh tell everyone! 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 bullets flat profile and the patented Flex Tip insert within its hollowpoint cavity