Any lethal weapon of any description from which any shot, bullet, or other missile can be discharged. Section 57 Firearms Act 1968
What is a Firearm?
A hand-fired weapon that does not contain any explosive. When trigger is pulled, pellet is expelled by release of compressed gas. Suitable for short-distance shooting.
A hand-fired weapon Includes pistols and revolvers Suitable for short-distance shooting
Automatically loading weapon. Capable of rapidly firing multiple rounds.
A weapon fired from the shoulder, with a rifled bore. Suitable for long-distance shooting.
Smooth bored barrel. Ammunition is small spherical pellets in a plastic cartridge. Suitable for short-distance shooting.
1) ID of a bullet, cartridge case, or other ammunition component as having been fired by or in a particular firearm. 2)The possibility of such ID can be attributed to specific machining processes used in the manufacture of firearms
Part of a firearm that loads, fires and ejects a cartridge
The metal tube through which the bullet is fired
Inside of the barrel 'Smoothbore' weapons (typically shot guns) have no rifling Most handguns and rifles have 'rifling'
The end of the barrel attached to the action
The end of the bullet is blunted
There is a hole in the bullet that creates expansion when a target is struck, creating more damage
The soft lead is surrounded by another metal, usually copper, that allows the bullet to penetrate a target more easily
- The front of the bullet is flattened
Intermediate between round-nose & wadcutter
The diameter of the bore measured from land to land, usually expressed in hundredths of an inch (.22cal) or in mm (9mm)
Lands are the metal inside the barrel left after the spiral grooves are cut to produce the rifling
Lands and Grooves
The spiral grooves cut inside a gun barrel that give the bullet a spinning motion
Also called a 'round' Made up of a case, primer, powder and bullet
A device for storing cartridges in a repeating firearm for loading into the chamber Also referred to as a 'clip'
Modern gun cartridges use 'smokeless' powder that is relatively stable, and leaves little residue when ignited
Volatile substance that ignites when struck to detonate the powder in a cartridge
Most modern pistols, revolvers, rifles and some shotgun barrels have rifling in their barrels. It consists of grooves cut or formed in a spiral nature, lengthwise down the barrel of a firearm.
Identify who fired a weapon, Matching weapons and comparing used bullets, Providing evidence in the reconstruction of events
Potential Applications of Forensic Science
Examine what happens to the bullet inside the barrel of a firearm, during flight and when it reaches its target
Examine hands or clothing for primer residue from a person who has fired a weapon
Analysis of gunshot residue
Examine any marks that may have been transferred to a bullet as it is fired from the weapon
Physical fits and microscopic comparisons
Examine an obliterated serial no. using chemicals
Determination of the serial number of the firearm
1) The firing pin presses a distinctive dent into the primer cup. 2) Imperfections on the breech get stamped on to the cartridge case. 3) The ejector mechanism marks the cartridge cases. 4) Gunshot residue can spray from the trigger hole on to the hands (and around wounds). 5) The position of a spent cartridge at a crime scene may indicate where the assailant was standing
1) Matching striation marks will identify a bullet with a specific gun. 2) No two guns have exactly the same internal marks or defects which are transferred to the bullet or its soft metal casing as it passes along the barrel. 3) The recovered bullet should be examined microscopically with a test fired bullet using a comparison microscope
Identifying Striation Marks
This compound was first synthesised in 1965 and its use as an iron reagent was first described by Stookey in 1970. It may be used as a reagent for the detection of trace amounts of ferrous metal on hands. FERROPRINT
The Ferrozine Test