A rifle cartridge is a type of ammunition designed for use in rifles. It typically consists of a bullet, gunpowder, and a casing that holds everything together. When the rifle's trigger is pulled, the firing pin strikes the primer at the base of the cartridge, igniting the gunpowder and propelling the bullet out of the barrel at high speed. Rifle cartridges come in various calibers, which refer to the diameter of the bullet. Common examples include the .223 Remington and .308 Winchester. Each caliber is designed for specific purposes, such as hunting or target shooting, and can vary in terms of range and accuracy.