muzzle velocity

speed at which a bullet is fired within the barrel of a firearm

For the computer video game, see Muzzle Velocity (computer game). A gun's muzzle velocity is the speed at which the projectile leaves the muzzle of the gun. Muzzle velocities range from subsonic (below 330 m/s / ~1080 ft/s) for some pistols to more than 1,800 m/s (~5910 ft/s) for tank guns firing kinetic energy penetrator ammunition. The latter velocity is close to the limit achievable with chemical propellants.
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Noun
1. the velocity of a projectile as it leaves the muzzle of a gun
(hypernym) speed, velocity