Muzzle velocity is a vector quantity which means it has direction and magnitude. Generally speaking, any velocity is classified as a vector quantity, a value with direction and magnitude. Velocity is the rate of change of the location of the object moving and is specified by its direction and speed. Since muzzle velocity is a velocity then it would surely be a vector quantity. Muzzle velocity is the speed of a bullet as it is leaving a muzzle of a gun in a the direction where the gun is pointed. It would have a value ranging from about 120 m/s to 370 m/s in muskets to 1200 m/s for modern rifles.