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4. Firearms
- The University Press of Kentucky
- Chapter
- Additional Information
FIREARMS Murders by firearms became common in the seventeenth century after various wars placed such weapons in the hands of the peasant class. Reluctant to return to their life of poverty, many former soldiers became highwaymen—an occupation they invented. Many victims died before anyone conceived of trying to match a gunshot to the person who fired it. Possibly the first recorded instance of this occurred in 1794 in county Lancashire, England. In conducting a postmortem examination of the victim's body, the surgeon discovered in the wound a wad of paper. In those days firearms were of the single-shot, flintlock variety, loading of which involved pouring gunpowder down the barrel, then dropping in the round lead bullet, followed by a wad of paper that was tamped down with a ramrod to pack the charge tightly. In this case the paper wadding had been driven into the wound along with the bullet (no doubt indicating a relatively close shot). When the paper was opened, it was found to be a piece from a street ballad. When a suspect was arrested in the case, authorities found in his coat the remainder of the ballad, which the piece from the wound matched exactly. This convinced the jury of his guilt, and the court sentenced him to death.1 So began the important branch of criminalistics concerned with forensic firearms evidence. BASIC ARMS AND AMMUNITION Firearms and the ammunition they use are of sufficient variety and complexity to require a brief discussion, complete with the basic nomenclature. 4 85 8 6 CRIME SCIENCE Firearms. Firearms may be divided into two main categories: handguns and shoulder firearms.2 As their name implies, handguns, also called pistols , are designed to be held in the hand. The simplest type is the singleshot pistol—that is, one that must be loaded and cocked for each firing.3 Antique flintlock and percussion pistols are of this type. (In percussion, or "cap-and-ball" firearms, a pull of the trigger and the resulting fall of the hammer discharge the explosive cap, which in turn ignites the powder . The percussion cap replaced the troublesome and somewhat unpredictable combination of flintlock and flash pan—the former showering sparks into a small amount of priming powder.)4 The .44-caliber Derringer pistol that John Wilkes Booth used to assassinate President Lincoln was of this single-shot percussion type (firing a ball that was homemade of Britannia metal, an alloy of tin).5 Other types of single-shot pistols include certain models used for training or target shooting,6 typical "zip guns" (homemade pistols),7 a clandestine "fountain-pen gun," and the notorious sawed-off shotgun.8 The great majority of pistols today are multiple-shot weapons, either revolvers or self-loading pistols. Revolvers take their name from their revolving cylinder, which has multiple chambers to hold the cartridges. Most revolvers are five- or six-shot. With a single-action revolver, the cylinder turns to the next chamber each time the gun's hammer is cocked by the thumb. A double-action model does not require manual cocking; each time the trigger is pulled, the hammer is cocked (and, simultaneously, the cylinder revolves to the next position), and then it is released, firing the cartridge. (Double-action revolvers may also be used in a singleaction fashion.) To load a revolver, the cylinder is opened, in most models either by pivoting the barrel downward (and with it the cylinder) or by swinging out the cylinder. These are known, respectively, as "top-loading " and "swing-out loading" designs.9 A self-loading pistol, also known as "autoloading" or (erroneously) "automatic," takes cartridges from a magazine, sometimes (erroneously) called a "clip," which is located in the handle of the pistol. With each firing, the pistol's own recoil energy moves the slide rearward, ejects the expended shell case, recocks the firing mechanism, and loads a new round into the firing chamber. This type of pistol may be fired as fast as the trigger is pulled, and is often termed a semiautomatic. A truly automatic pistol fires continuously while the trigger is held down.10 Unlike handguns, shoulder firearms have long barrels and are meant for use by both hands. The main types are rifles and smoothbore arms. Rifles take their name from their rifled barrels. Rifling is a set of spiral [44.212.39.149] Project MUSE (2024-03-28 13:16 GMT) FIREARMS 87 grooves cut into the interior surface of the barrel; the...