Firearms Examinations

Crime Detection: Scientific Crime Investigation Firearms Examinations

Introduction to Firearms Examinations

Firearms are identified through microscopic imperfections that are produced inadvertently in gun barrels during manufacture. Subsequent use and wear contribute further to a weapon’s individuality. A bullet fired from a pistol or rifle, therefore, has impressed on its surface the individual characteristics of the barrel through which it was fired. Other parts of the gun also possess individual characteristics. The firing pin, breech face, extractor, and ejector come in contact with the cartridge case; hence, cartridge cases may be scarred with distinctive markings that can be identified with a particular gun (see Small Arms).

The material products of gunpowder combustion are ejected from the muzzle of a gun in the form of a cone. If the distance between the gun and the object through which the bullet passes is within certain limits, a microscopic or chemical examination of the area surrounding the bullet hole may establish the distance from which the gun was fired at the victim (see Ballistics).” (1)

Resources

Notes and References

• Information about Firearms Examinations in the Encarta Online Encyclopedia

Guide to Firearms Examinations

In this Section

Crime Detection, Crime Detection History, Surveillance, Interrogation, Crime Detection Records,

Scientific Crime Investigation, Firearms Examinations, Serological Investigations, Investigation Toxicology ,Hairs and Fibers Crime Investigation, Crime Mineralogical Investigations, Crime Metallurgical Investigations and Crime Document Examination.