Colorado POST Practice Exam

How can a bullet be matched to the gun it was fired from?

1. By examining the weight of the bullet

2. By comparing the caliber of the bullet

3. By matching imperfections in the barrel to the bullet's impressions

4. By looking at the ammunition used

The correct answer is: By matching imperfections in the barrel to the bullet's impressions

A bullet can be matched to the specific gun it was fired from primarily by examining the unique markings and imperfections that occur on the bullet as it travels down the barrel of the firearm. Every firearm has a distinctive barrel, which leaves unique striations and impressions on the bullet's surface when it is fired. These markings result from the microscopic irregularities in the barrel, which are influenced by the manufacturing process and wear over time. During forensic analysis, experts compare these striations and the overall impression left on the bullet with test bullets fired from a suspected firearm. If the markings match, it provides strong evidence that a specific bullet was discharged from that particular gun. This technique is a critical method in firearms identification and plays a significant role in criminal investigations. The other options don’t provide sufficient means for reliable matching of a bullet to a firearm. While caliber refers to the diameter of the bullet and can indicate a category of firearm, it does not uniquely identify the specific gun. Weight can vary but is not a differentiating factor for gun matching. Similarly, while knowing the type of ammunition can be relevant in an investigative context, it does not enable the determination of the precise firearm used.