Muzzle Energy - Calculating Muzzle Energy

Calculating Muzzle Energy

Care must be taken when using this formula that consistent units are used.

• In SI units:
  • If the mass, m, is in kilograms and the speed, v, is in metres per second, the calculated muzzle energy, E_k, will be in joules.
  • If the mass, m, is in grams and the speed, v, is in kilometres per second, the calculated muzzle energy, E_k, will be in kilojoules.
• In American engineering units:

• Mass, m, is usually given in grains and the speed, v, in feet per second but kinetic energy, E_k, is typically given in foot-pound force (abbreviated ft-lbf). Most sporting arms publications within the United States report muzzle energies in foot-pound force. If m is specified in grains and v in feet per second, the following equation can be used, which gives the energy in foot-pound force:

• When publishing kinetic energy tables for small arms ammunition, an acceleration due to gravity of 32.163 ft/s2 rather than the standard of 32.1739 ft/s2 is used. The formula therefore becomes

The bullet energy, remaining energy, down range energy and impact energy of a projectile may also be calculated using the above equations.