Firearm muzzle velocities range from approximately 120 m/s (390 ft/s) to 370 m/s (1,200 ft/s) in black powder muskets, to more than 1,200 m/s (3,900 ft/s) in modern rifles with high-velocity cartridges such as the

The calculation that a .223 round fired from an AR-15 can reach speeds of up to six football fields in a second was made using a 55 grain .223 Remington full metal case round fired at a horizontal trajectory. The muzzle velocity of this round is 3,240 feet per second.