Subsonic ammunition is ammunition specifically designed to not break the sound barrier and is best utilized in a suppressed weapon. A bullet that breaks the sound barrier will leave a distinct loud “crack” downrange. That sounds simple enough. But, the sound barrier is not a static barrier. It will fluctuate based on several factors including temperature, humidity and altitude. Therefore, at a temperature of 68° F (20° C), with low humidity, and at sea level the sound barrier is around 1,125 fps. Keeping this number in mind we try to load our ammunition to achieve speeds of 950 – 1,050 fps. Why would we want to load ammunition at around 1,000 fps is the sound barrier is at 1,125 fps? Well, the sound barrier is constantly fluctuating and we have customers utilizing the same ammunition in different environments all around the world. We need the ammunition to not break the sound barrier in all these varying conditions. Also, no two firearms are the same. This includes rifles off the same production lines. Barrels have a unique individuality and will handle ammunition differently. Barrel lengths also differ from firearm to firearm. The same ammunition fired from a 20” barrel will not travel the same speed if it was to be fired out of a 16” barrel. This is not extremely important when you are utilizing high velocity (supersonic) ammunition, but with subsonic it is very important. Our ammunition was original developed for military operators who rely on the low sound signature to stay alive during covert missions. The projectile breaking the sound barrier, to them, potentially means the difference between life and death.