Muzzle flash

Muzzle flash is the light — both visible and infrared — created by a muzzle blast, which is caused by the sudden release and expansion of high-temperature, high-pressure gases from the muzzle of a firearm during shooting. Both the blast and flash are products of the exothermic combustion of the propellant (gunpowder), and any remaining unburned powders reacting with ambient air. The size and shape of the muzzle flash is dependent on the combustion energy of propellant being used, the amount of combustible ejecta remaining, and any devices attached to the muzzle (such as a flash hider, suppressor or muzzle shroud). Muzzle flash can be broken down into five distinct components. The muzzle glow is a reddish glow that is visible before the bullet leaves the barrel. It glow is created by superheated gases that have leaked past the projectile and have exited the barrel ahead of it. The primary flash is caused by superheated propellant gases exiting the firearm behind the projectile, which radiates its energy to the surroundings partly as visible light. Although amongst the brightest of the flashes, the heat of the primary flash dissipates very quickly, and thus is usually not distinctly noticeable. The intermediate flash is caused by shock waves created by the high speeds of the escaping gases and projectile, and appears as a reddish disc-shaped in front of the muzzle. The secondary flash appears farthest from the muzzle as a large white or yellow fireball, and is caused by a newly ignited oxidation of incompletely combusted ejecta when mixed with abundant oxygen in the surrounding atmosphere. Following the dissipation of the muzzle flash, partially unburnt powder or other heated materials (e.g. dislodged lead, copper and/or carbon foulings) can be further ejected from the muzzle and appear as airborne residual sparks. Muzzle flashes create distinct signatures that can be located using infrared imaging technology. Technology is being developed to detect enemy muzzle flashes before the projectile reaches its target.