A flash suppressor is a device attached to the muzzle of a rifle that reduces the visible light signature emitted from the gun barrel when fired.
The US military began using flash suppressors in World War II to help conceal soldiers from the enemy. Today, militaries around the world use them for the same reason—to make it more difficult for enemies to spot troops in the dark and to avoid giving away their positions.
Flash suppressors also have benefits for civilian shooters. They reduce muzzle climb and recoil, making it easier to stay on target for follow-up shots. And they make shooting in low-light conditions safer because they reduce the chances of being temporarily blinded by your own weapon’s flash.
There are a few different types of flash suppressors on the market, but they all work by redirecting the gases that escape from the barrel when a round is fired. This gas expansion cools and quenches the hot gases, reducing the amount of light that’s emitted.
Some flash suppressors also have ports or slots cut into them. These help to disperse the gas and further reduce the flash signature.