The firing pin is generally mechanically restrained and, when the firearm is cocked, the firing pin spring is compressed. This round consists of an outer cartridge case, a bullet, some form of propellant, and a percussion cap. Finally, terminal ballistics, also known as impact ballistics, refers to the study of the projectile striking a target.Īlthough there is a wide range of types of firearm, the basic theory behind how a projectile is fired is fairly generic – the weapon aims to convert chemical energy into kinetic energy in order to expel a projectile from the firearm.Ī round is first loaded and locked into the breach. Following this, external ballistics deals with the bullet’s flight between leaving the firearm and striking a target. Internal ballistics refers to the processes inside the firearm, the minute space of time between the shooter pulling the trigger and the bullet exiting the muzzle of the gun. The study of firearms and firearm ballistics is often divided in internal, external and terminal ballistics. During investigations in which the use of firearms is suspected, a number of artefacts may be collected for examination, including firearms, cartridge cases, bullets, live ammunition, trace materials, and any material damaged by a projectile. This area of study examines the path of a bullet from when it leaves the firearm up until it strikes the target. Closely linked to this is ballistics, which relates to the flight path of projectiles, often associated with forensic science during the investigation of firearms.
Firearm investigation is a specialty of forensic science focusing on the examination of firearms and related subjects.