Simply put, a suppressor is a tube with a series of partitions inside that trap the expanding gases and slow their release into the air. This reduces the pressure wave, and thus the noise, the firearm creates.
The full technical explanation involves physics, metallurgy, heat transfer, the chaotic movement of gases under pressure, and we’ll skip that.
Making a suppressor is both easy and difficult. It is easy, in that pretty much anything you put over the end of the muzzle will dampen noise. (Which can, in some instances and designs, be against the law without proper paper-work.) It is difficult in that what you use to dampen noise can degrade accuracy, cause difficulties aiming, and can be inconvenient, messy and just plain ugly.
Suppressor designers and manufacturers work hard…
