![Rifling - Grooves Rifling - Grooves](https://jg3ca7.p3cdn1.secureserver.net/wp-content/uploads/2019/03/Rifling-Grooves.jpg)
Grooves:
Grooves are the spiral cuts or impressions in the bore of a firearm that cause a bullet to spin as it moves through the barrel. The grooves are technically the portion of the bore in a rifled barrel that have been machined away.
See lands.