When using subsonic ammunition, the bullet is going far slower - and often won't be stabilized correctly. Most barrels are designed with twist rates that are optimized for a specific caliber of bullet travelling at a standard velocity for that caliber.Subsonic ammunition just doesn't have enough pressure to make the rifle run correctly. With semi-automatic rifles, such as the AR-15, they typically won't operate correctly unless they have enough blowback.While it's true that shooting subsonic ammunition is going to be quieter, it isn't always a good idea for a variety of reasons:
Why is it a Bad Idea to Always Shoot Subsonic Ammo?
In other words, even though it isn't that loud in the grand scheme of things, the supersonic crack can make a real difference to how much you enjoy shooting.
When people first start learning about suppressors, one of the first 'facts' they learn is typically that you can't suppress supersonic ammunition.Īfter a bullet is fired, it creates pressure waves as air is displaced along its path.