A bullet is a primitive ballistic weapon made of solid metal. Typically, a bullet, either cased or caseless, is combined with it's propellant in some way and this is termed a cartridge. Bullets may be fired from any of the following common weapons: autocannon, machine gun, pistol, or rifle.

Although they share much in common a bullet should not be confused with a slug.


In most cultures, the concept of bullets predates firearms. The earliest bullets were made of stone, later metal, and were propelled by slings or some kind of tension or torsion devices (such as catapults). Upon the advent of firearms these same bullets were placed in front of explosive charges, forming a cartridge, near the closed end of a tube. Bullets changed only slightly in their early history and then evolved rapidly nearing the height of their use, departing from spherical rounds to conical or pointed bullets.

The rapidity of development only varies by society or species but progression is otherwise universal.


Modern bullets are little changed from their past incarnations, regardless of the culture utilizing them. They are still masses of metal with a pointed tip and a jacketed shank. Although usually caseless a number of large bore types may still be cased when cost is an issue and efficiency is not required. Some kinds of bullets may be made of special ceramics intended to be harder than the type of armor they are expected to come into contact with. The largest deviation from traditional bullets are self-propelled varieties.


Bullets have a number of advantages. Firstly, they are compact and inexpensive and excel against soft targets (unarmored organic creatures) as weapons. Accelerating them is simple and energy costs are kept low when used. They can be made of exotic materials to boost their performance but bullets are usually made of lead or uranium to save on cost.


Bullets also have several disadvantages. Firearms have an upper limit for the speed of their projectiles and therefore the speed of a bullet from a conventional firearm can only be so high. Propellant efficiency is also variable. Additionally, rapid loss of kinetic energy occurs during the bullet's flight to the target and environmental effects compound accuracy issues.


Most modern bullets are caseless. That is, the bullet itself is buried in a block of high explosive. However, when efficiency and logistics are not an issue cased rounds still see some use. Despite the more complex firing mechanisms required to use them and the added weight of the metal casings themselves, they allow for more specialized types of bullets to be used, thus keeping them relevant. Most all contemporary conventional firearms utilize caseless ammunition, however, due to the smaller logistics footprint.