Rifling in the Rifle or Handgun Bore

A bullet fired from a rifle or handgun has a spiral spin that keeps it point-first in flight, increasing accuracy and distance. This is achieved by the rifling inside the barrel, from which the rifle got its name. The barrel is thick and has spiraling grooves cut or pressed into the bore. The ridges of metal between the grooves are called lands. Together, the grooves and lands make up the “rifling.”

Originally, rifling was an attempt made by an unknown barrelsmith to reduce the problem of fouling caused by black powder. The first grooves were cut straight down the length of the barrel. When fouling continued to build up, a slight twist was added to the grooves with the intent of adding a scrubbing action. The fouling problem was never solved, but a major discovery was made. The "slight twist" caused the bullet to spin like a properly thrown football. The spinning bullet resulted in increased accuracy over greater distances.