The markings on a bullet/projectile that are unique to each weapon are called
a. Breechmarks
b. Firing pin markings
c. Striations
d. Lands and grooves
The correct answer and explanation is:
The correct answer is c. Striations.
Striations refer to the unique markings left on a bullet or projectile as it travels down the barrel of a firearm. These markings are created by the microscopic imperfections and grooves inside the barrel, which are often intentionally made during the manufacturing process. When a bullet is fired, it engages with these grooves, and as it passes through, tiny scratches or striations are transferred onto the surface of the bullet. These markings are as unique to the barrel of the firearm as fingerprints are to an individual.
The striations are a critical component in forensic ballistic analysis because they can be used to link a bullet found at a crime scene to a specific weapon. By comparing the striations on a bullet to those produced by a suspected weapon, forensic experts can determine whether the bullet was fired from that firearm.
Breechmarks (a) refer to markings left on the casing of a fired cartridge, often caused by contact with the breech face of the gun. Firing pin markings (b) are indentations left by the firing pin when it strikes the primer of the cartridge. Lands and grooves (d) describe the rifling inside the barrel itself, which imparts spin to the bullet for stability but is not directly involved in the unique identification of a specific weapon like striations.
Through ballistic testing and comparison, forensic experts can use striations to help identify firearms involved in criminal activity, which plays an essential role in criminal investigations.