rifling

Rifling refers to the spiral grooves cut inside the barrel of a firearm. This process, known since at least the 15th century, imparts a spin to the projectile, significantly improving its accuracy and range compared to smoothbore barrels.12

Early firearms had smooth barrels, but the loose fit of the projectile caused wobbling, leading to inaccurate shots beyond short distances. The discovery that spiral grooves stabilized bullets through gyroscopic spin was a major advancement. However, loading rifled weapons was initially slower because the bullet had to fit tightly into the grooves. Solutions like greased patches and later the Minié ball, which expanded upon firing, addressed this issue. The development of breech-loading mechanisms and metallic cartridges further revolutionized rifle design, leading to the bolt-action and eventually the assault rifle prevalent today.32