Which term describes the marks left on a bullet as it is fired from a gun?

The term that accurately describes the marks left on a bullet as it is fired from a gun is striated markings. Striation occurs when the bullet comes into contact with the barrel during firing, resulting in unique patterns that can be used to match a bullet to a particular firearm. Each firearm has its own distinct barrel characteristics, leading to variations in these striated markings, which are crucial for forensic investigations.

Barrel impressions refer more generally to the outline or shape of the gun barrel rather than the specific markings on the bullet. Groove impressions, while they are part of the bullet-making process, focus more on the design of the barrel itself rather than the resultant markings on the bullet. Fired trajectory pertains to the path a bullet takes after being fired, which does not relate directly to the marks it leaves on the bullet.