What Branch of Forensics Studies Gun Bullets?

The branch of forensics that specifically studies gun bullets and related evidence is forensic ballistics. This specialized field plays a critical role in criminal investigations by analyzing firearms, ammunition, and other ballistic evidence found at crime scenes.

Understanding Forensic Ballistics

Forensic ballistics involves the detailed examination of evidence from firearms that may have been used in a crime. When a bullet is fired from a gun, the firearm imparts unique microscopic marks on both the bullet itself and the cartridge case. These distinctive marks are often referred to as "ballistic fingerprints" because, much like human fingerprints, they can be unique to a particular firearm.

Key aspects of forensic ballistics investigation include:

• Bullet Examination: Analyzing the striations (scratch marks) left on the bullet by the rifling inside the gun's barrel. These marks can help determine the type of firearm used and, in many cases, link a bullet to a specific weapon.
• Cartridge Case Analysis: Examining impressions left on the spent cartridge case, such as:
  • Firing Pin Impressions: Unique marks left by the firing pin hitting the primer.
  • Breech Face Marks: Impressions from the part of the firearm that supports the cartridge base.
  • Ejector and Extractor Marks: Scratches and deformations caused by the mechanisms that remove the spent case from the firearm.
• Firearm Analysis: Testing suspected firearms to compare their unique markings with evidence found at a crime scene.
• Trajectory Analysis: (Often conducted by ballistics experts) Determining the path of a bullet, which can help reconstruct the events of a shooting.

How Ballistic Fingerprints Aid Investigations

The concept of "ballistic fingerprints" is fundamental to forensic ballistics. Every firearm leaves a unique set of microscopic marks due to manufacturing imperfections and wear patterns. By meticulously comparing the marks on a crime scene bullet or cartridge case with those produced by a suspect firearm under controlled conditions, forensic ballistic experts can:

• Identify a specific weapon: Determine if a particular firearm was used in a crime.
• Link multiple crimes: Connect different crime scenes if the same firearm was used.
• Determine firearm type: Identify the make, model, and caliber of the weapon involved.
• Corroborate witness testimonies: Provide objective evidence regarding the events of a shooting.

This detailed examination is crucial for law enforcement in solving crimes and providing critical evidence for legal proceedings. For more in-depth information on the scientific principles behind firearms and toolmark examination, you can refer to resources from institutions like the NIST Firearms and Toolmarks section.