What is the purpose of a bullet jacket?

The purpose of a bullet jacket is primarily to keep the bullet from jamming, melting, or disintegrating during its passage through the barrel and into the target. Bullet jackets, often made of metal like copper, serve to protect the softer lead core of the bullet. This protective outer layer helps maintain the integrity of the bullet, preventing deformation and ensuring that it remains stable when fired. Additionally, the jacket reduces friction between the bullet and the gun's barrel, which helps improve overall performance, including reliability when cycling through a firearm.

Maintaining structural integrity is essential to ensure efficient energy transfer upon impact, which is vital for maintaining the effectiveness of the projectile. While factors like accuracy, penetration, and speed are influenced by various aspects of the bullet's design, the bullet jacket is specifically designed to enhance reliability and performance by preventing issues related to melting or disintegration.