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Ballistics

• Forensic ballistics involves analysis of bullets and bullet impacts to determine the type. Separately from ballistics information, firearm and tool mark examinations involve analyzing firearm, ammunition, and tool mark evidence in order to establish whether a certain firearm or tool was used in the commission of a crime.

• In 1835, Scotland Yard’s Henry Goddard became the first person to use physical analysis to connect a bullet to the murder weapon.

• Bullet examination became more precise in the 1920s, when American physician Calvin Goddard created the comparison microscope to help determine which bullets came from which shell casings. 

• In the 1970s, a team of scientists at the Aerospace Corporation in California developed a method for detecting gunshot residue using scanning electron microscopes.

There are 4 different types of ballistics

• Internal ballistics, the study of the processes originally accelerating the projectile, for example the passage of a bullet through the barrel of a rifle;
• Transition ballistics, (sometimes called intermediate ballistics) the study of the projectile’s behavior when it leaves the barrel and the pressure behind the projectile is equalized.
• External ballistics, the study of the passage of the projectile through space or the air; and
• Terminal ballistics, the study of the interaction of a projectile with its target, whether that be flesh (for a hunting bullet), steel (for an anti-tankround), or even furnace slag (for an industrial slag disruptor)