What does 'degree of twist' refer to in the context of bullet analysis?

The term 'degree of twist' in bullet analysis specifically refers to the pattern of rifling in the barrel of a firearm. Rifling consists of helical grooves cut into the bore of a gun, which imparts a spin to the bullet as it is fired. This spin stabilizes the bullet during flight, improving accuracy and distance. The 'degree of twist' indicates how tightly these grooves spiral around the barrel—essentially, it refers to the rotation rate of the bullet as it exits the weapon.

The twist can vary between different firearms, with some exhibiting a faster twist and others a slower one. Analyzing the degree of twist is crucial in forensic ballistics, as it helps to match a bullet found at a crime scene with a specific firearm, aiding in investigations. Understanding this concept is key for forensic analysts when examining bullet markings and connecting them to a weapon.