Exam 9: Firearms, Tool Marks, and Other Impressions

DRUGFIRE was developed by the ________.

Generally, the gauge of a shotgun is ________ to the diameter of its barrel.

Dust imprints found at a crime scene can be lifted using:

The hook cutter rifling method is still used today.

The SEM approach for primer residue detection is its enhanced specificity over hand swabbing.

Match the word in Column 1 to its definition in Column 2. Each answer can only be used once. A)The cut or low-lying portions between the lands in a rifled bore B)An interior constriction placed at or near the muzzle end of a shotgun's barrel to control shot dispersion C)A discipline mainly concerned with determining whether a bullet or cartridge was fired by a particular weapon D)A chemical test used to develop patterns of gunpowder residues around bullet holes E)The rear part of a firearm barrel F)The mechanism in a firearm that throws the cartridge or fired case from the firearm G)The mechanism in a firearm by which a cartridge or fired case is withdrawn from the chamber H)The spiral grooves formed in the bore of a firearm barrel that impart spin to the projectile when it is fired I)The diameter of the bore of a rifled firearm, usually expressed in hundredths of an inch or millimeters J)Size designation of a shotgun, originally the number of lead balls with the same diameter as the barrel that would make a pound. The only exception is the .410 shotgun, in which bore size is 0.41 inch. K)The raised portion between the grooves in a rifled bore L)The interior of a firearm barrel M)The process of determining the distance between the firearm and a target, usually based on the distribution of powder patterns or the spread of a shot pattern -Extractor

The parts of a firearm that leave impressions on a cartridge case that constitute class characteristics of that weapon are the firing pin, the breechface mark, the ejector, and the extractor.

The reason grooves are rifled into the bore of a gun is so that a:

Match the word in Column 1 to its definition in Column 2. Each answer can only be used once. A)The cut or low-lying portions between the lands in a rifled bore B)An interior constriction placed at or near the muzzle end of a shotgun's barrel to control shot dispersion C)A discipline mainly concerned with determining whether a bullet or cartridge was fired by a particular weapon D)A chemical test used to develop patterns of gunpowder residues around bullet holes E)The rear part of a firearm barrel F)The mechanism in a firearm that throws the cartridge or fired case from the firearm G)The mechanism in a firearm by which a cartridge or fired case is withdrawn from the chamber H)The spiral grooves formed in the bore of a firearm barrel that impart spin to the projectile when it is fired I)The diameter of the bore of a rifled firearm, usually expressed in hundredths of an inch or millimeters J)Size designation of a shotgun, originally the number of lead balls with the same diameter as the barrel that would make a pound. The only exception is the .410 shotgun, in which bore size is 0.41 inch. K)The raised portion between the grooves in a rifled bore L)The interior of a firearm barrel M)The process of determining the distance between the firearm and a target, usually based on the distribution of powder patterns or the spread of a shot pattern -Lands

Match the word in Column 1 to its definition in Column 2. Each answer can only be used once. A)The cut or low-lying portions between the lands in a rifled bore B)An interior constriction placed at or near the muzzle end of a shotgun's barrel to control shot dispersion C)A discipline mainly concerned with determining whether a bullet or cartridge was fired by a particular weapon D)A chemical test used to develop patterns of gunpowder residues around bullet holes E)The rear part of a firearm barrel F)The mechanism in a firearm that throws the cartridge or fired case from the firearm G)The mechanism in a firearm by which a cartridge or fired case is withdrawn from the chamber H)The spiral grooves formed in the bore of a firearm barrel that impart spin to the projectile when it is fired I)The diameter of the bore of a rifled firearm, usually expressed in hundredths of an inch or millimeters J)Size designation of a shotgun, originally the number of lead balls with the same diameter as the barrel that would make a pound. The only exception is the .410 shotgun, in which bore size is 0.41 inch. K)The raised portion between the grooves in a rifled bore L)The interior of a firearm barrel M)The process of determining the distance between the firearm and a target, usually based on the distribution of powder patterns or the spread of a shot pattern -Rifling

For each of the impressions listed below, determine which characteristics are class characteristics and which are individual characteristics. a. Screwdriver pry mark: 0.5 inch wide, filings of stainless steel imbedded in mark, rounded edges, center half-circle groove, 3 wide striations near one edge, 7 narrow striations near one edge b. Two-dimensional footwear impression: Nike brand, 11 inches long, wear pattern on back outside edge, 4 inches wide at arch, gouge at back heel, "Nike Air" imprinted on arch c. Recovered bullet: .22 caliber, deep striation in one land, left-handed twist, 13 fine striations in one groove, 5 grooves around periphery, 79% lead composition

Two procedures used to preserve impressions that cannot be submitted to the laboratory are lifting and casting.

Which of the following statements is true?

What two methods are used to preserve shoe and tire marks impressed into soft earth? Why is it important to conduct both procedures on the impression?

Which is NOT a class characteristic of a suspect's sneaker?