Module 4 - Forensic Ballistics
Lesson 3 - Testing for Gunshot Residue
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In the 1880s, Alfred Nobel made his fortune by developing dynamite and a smokeless gunpowder called ballistite. When Nobel died in the late 1800s, he left the majority of his estate to establish the Nobel Prizes to be awarded annually to individuals who helped to better mankind. Apparentlly Nobel did this after reading an article in a French newspaper that condemned him for inventing dynamite and gunpowder by stating that he "…became rich by finding ways to kill more people faster than ever before." |
The Evolution of Firearms and Gunpowder
Firearm effectiveness has increased dramatically since the first firearms were developed more than 600 years ago. Fixed ammunition, which consisted of a primer, gunpowder, and projectile contained within a shell casing, made its first appearance in the American Civil War in the 1860s. These early firearms utilized a single action firing mechanism that produced a relatively slow rate of fire because the weapon had to be reloaded after each round was fired. However, their increased muzzle velocity and higher degree of accuracy over long distances resulted in a tremendous increase in the destructive capabilities of rifles and handguns.
Traditional varieties of gunpowder led to rapid residue build-up in the interior components, causing a weapon to jam after short periods. Semi-automatic rifles and automatic weapons (machine guns) became prominent with the advent of higher grades of gunpowder. Further refinements were made during both World Wars, which led to the development of reliable ammunition with smokeless gunpowder and precision weapons with high rates of fire. This has translated into the mass adoption of semi-automatic handguns by law enforcement agencies as the use of revolvers was phased out in recent years.
A Gunpowder Horn
Gunpowder is of two types: black powder and smokeless powder. Both burn very rapidly and release large amounts of gas in the process. The pressure from the gases generated inside the gun barrel is sufficient to propel a bullet, but it does not destroy the gun barrel.
| In 9th century China, the oldest known explosive consisting of sulphur, charcoal, and saltpetre (nitre, potassium nitrate) was developed. |