Question 1

Which of the following methods is a non-destructive method of determining the presence of several metals in an experiment in a gunshot residue (GSR) sample?&#10;A) AA&#10;B) color tests&#10;C) XRF&#10;D) flame test

Accepted Answer

XRF is a non-destructive method that can identify the presence of several metals in a GSR sample by measuring the x-rays emitted by the sample in response to being bombarded by high-energy photons. AA and flame tests are destructive methods that require the sample to be burned, and color tests can be destructive depending on the type of test used.

Question 2

The caliber is determined from measuring _____.&#10;A) between opposite lands&#10;B) between opposite grooves&#10;C) direction of twist&#10;D) measuring mass&#10;E) all of the above

Accepted Answer

The caliber of a firearm is determined by measuring the diameter between opposite lands in the barrel.

Question 3

Which of the following is evaluated in examinations of cartridge cases?&#10;A) firing pin impression&#10;B) ejector impression&#10;C) extractor impression&#10;D) breechblock impression&#10;E) all of the above

Accepted Answer

All of the listed features (firing pin impression, ejector impression, extractor impression, and breechblock impression) can be evaluated in examinations of cartridge cases to provide information about the firearm and ammunition used in a crime.

Question 4

Which of the following would be considered a class characteristic of a firearm?&#10;A) direction of twist&#10;B) weight&#10;C) caliber&#10;D) number of lands and grooves&#10;E) all of the above

Accepted Answer

Class characteristics are features that are common to a group of items, rather than unique to a specific item. In the context of firearms, direction of twist, caliber, and number of lands and grooves are all characteristics that can be used to categorize a firearm into a specific class. These features are determined by the manufacturer and are consistent among all firearms of the same model, making them class characteristics. Weight, while it can vary slightly due to manufacturing differences or modifications, is generally not considered a defining class characteristic in forensic ballistics.

Question 5

Which of the following is a presumptive test for gunshot residue?&#10;A) Iodine fuming&#10;B) Kastle-Meyer&#10;C) Griess test&#10;D) Duquenois-Levine

Accepted Answer

The Griess test is a presumptive test for gunshot residue because it detects nitrites, which are common components of the residues left by the discharge of firearms.

Question 6

Which microscope is best suited to the initial evaluation of evidence such as cartridge cases?&#10;A) SEM&#10;B) compound light microscope&#10;C) comparison microscope&#10;D) stereoscope

Accepted Answer

The stereoscope is best suited for the initial evaluation of evidence such as cartridge cases. It allows for a three-dimensional view of the evidence at a low magnification, making it easier to quickly identify any distinguishing characteristics or features. Additionally, it is easier to use and requires less sample preparation compared to other types of microscopes such as SEM or compound light microscopes.

Question 7

The lands and grooves in a gun's barrels are formed by a process termed ____.&#10;A) calibering&#10;B) rifling&#10;C) breechblocking&#10;D) microgrooving

Accepted Answer

The lands and grooves in a gun's barrel are formed by the process of rifling, which involves cutting spiral grooves into the bore. This creates a rotational spin on the bullet as it travels down the barrel, improving accuracy and range. Calibering refers to measuring the diameter of the barrel, while breechblocking and microgrooving are not directly related to the formation of lands and grooves in the barrel.

Question 8

Which of the following materials will have only class characteristics?&#10;A) unfired bullets&#10;B) toolmarks&#10;C) fingerprints&#10;D) fired bullets

Accepted Answer

Unfired bullets have class characteristics because they are mass-produced and share common features like size, shape, and design, which are not unique to a single item.

Question 9

To determine if a bullet's breech face marks originated from a specific firearm, what is the testing procedure? Perform a ____ for comparison to the evidence markings.&#10;A) test fire with the evidence bullet&#10;B) test fire with a bullet of the same caliber from the same manufacturer as the evidence&#10;C) test fire with a bullet of the same caliber of any manufacturer&#10;D) compare the breech marks from the weapon and evidence directly

Accepted Answer

The correct procedure involves test firing a bullet of the same caliber from the same manufacturer as the evidence bullet. This ensures that the comparison is made under conditions as similar as possible to those of the evidence bullet, allowing for a more accurate assessment of whether the breech face marks on the evidence bullet originated from the specific firearm in question.

Question 10

In firearms analysis, firing pin markings would be found on the _____.&#10;A) fired bullets&#10;B) cartridge casing&#10;C) paper wad&#10;D) gunpowder&#10;E) all of the above

Accepted Answer

Firing pin markings are made on the cartridge casing by the firing pin, which strikes the primer located at the base of the cartridge casing. The other options listed would not bear firing pin markings.

Question 11

How does shotgun ammunition differ from that fired with a revolver? How do the resulting markings on the spent ammunition differ?

Accepted Answer

The answer of How does shotgun ammunition differ from that...

Question 12

List three features of bullets used in individualization.

Accepted Answer

The answer of List three features of bullets used in...

Question 13

List three features of cartridge casings used in individualization.

Accepted Answer

The answer of List three features of cartridge casings used...

Question 14

Explain the use and value of databases in firearms analysis.

Accepted Answer

The answer of Explain the use and value of databases...

Question 15

List chemical tests to detect and identify propellants and explosives used in firearms.

Accepted Answer

The answer of List chemical tests to detect and identify...

Deck 13: Firearms