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Fundamentals of Ballistics

Copyright © Gunther Dyckmans (2007 - 2015)

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Firearms are weapons. Police and defence forces are equipped with firearms but they are not the only potential users. It is estimated that within the United States and the European Union, more than 300 million firearms are owned by civilians. Each nation has its own weapon legislation. Each individual is expected to know and to obey the law.


From a technical point of view, the main goal of a firearm is to safely propel a projectile such that it starts its trajectory towards the target with the appropriate speed. Depending upon the application, this speed ranges from a few hundred metres per second to almost 2000 m/s. Such high speeds are necessary in order for the projectile to reach its target and/or to hit it with sufficient remaining kinetic energy.

Although they date back to the fourteenth century, the functioning principle of firearms has remained unchanged.

The projectile is accelerated through the firearm’s bore. This is the interior part of the barrel. The diameter of the bore is known as the weapon’s calibre. If the projectile is loaded into the firearm from the rear, then the combustion chamber is closed by a bolt or a breech mechanism.


Kinetic energy

Kinetic energy is equal to half the mass multiplied by the velocity squared i.e. Ekin = 0.5 x m x .


0.5 x 80 x 10² = 0.5 x 0.008 x 1000² = 4000 joules → a sprinter in action (m = 80 kg; v = 36 km/h = 10 m/s) has about the same amount of kinetic energy as a high speed bullet fired from a rifle (m = 8 grams = 0.008 kg; v = 1000 m/s).

A sprinter or a bullet having the same kinetic energy provoke completely different effects when they hit a person → the concentration of kinetic energy per unit area is extremely important in terminal ballistics.



1000 m/s = 3600 km/h = 2237 mph = 1944 knots.


A 9 mm bullet fired from a pistol reaches its target at 20 m distance after 0.06 seconds i.e. 60 milliseconds; the reaction time of a top-class athlete approaches 150 milliseconds → it is practically impossible to avoid the bullet’s impact (for this example).

A geostationary satellite orbiting the earth has a speed of approximately 11,000 km/h, so it moves much faster than projectiles → the impact of space debris or meteoroids on satellites can have devastating effects.


Projectiles fly fast !

With its total length of about five metres, its calibre of 640 millimetres and its net mass of more than twelve tons, the “Dulle Griet” is the largest Western wrought iron bombard that remains from the Middle Ages. It fired stone projectiles of almost 300 kilogrammes. Its maximum range was about 1200 metres. The  “Dulle Griet” can be viewed by the public in the Belgian city of Ghent.

Sample Page

- The firearm has a combustion chamber which is filled up with propellant;

- The propellant is ignited, burns and produces gases;

- The combustion gases exert pressure upon the projectile’s base and push the projectile forward.