A shell is a payload carrying ballistic projectile, fired from an autocannon, cannon, gas gun or other large firearms. Shells are fired using a chemical propellant of some kind with which they are generally conjoined to by a case, forming a cartridge. Gas gun cartridges are normally caseless.

Shells are commonly fired from starship grade weapons due to their destructive potential.


The shell is usually closely associated with ancient gunpowder cannons in most cultures. Therefore, the existence of shells is tied directly to firearms. Some scholars contend that the first shells were actually hurled from catapults in the form of pottery filled with naptha (a mixture of petroleum and resin). Regardless of the origins of shells they have all evolved in similar ways over time to be one of the most deadly weapons organisms can turn on one another. This means that, by extension, firearms remain in widespread use.


Modern shells are far more sinister than their historical counterparts. While most still carry an explosive charge to the target - very destructive charges - others still bear specialized payloads, including nuclear warheads. Unlike the bullet the shell is nominally a cased weapon. This is because of the large amount of propellant needed to fire the shell over long distances and the need for a safer, more compartmentalized system. Chemical fuses have given way to electronic varieties in modern shells owing to their accuracy.


Shells have a few distinct advantages: primarily, they are an inexpensive way to deliver destructive firepower to a target without the power requirements of more energetic weapons while maintaining a fair modicum of accuracy and rate of fire. Their modular nature also means that firearms are flexible without straining the logistics capabilities of the operator.


Limited accuracy and range are issues which plague all firearms as a matter of course. Large firearms using shells sport much greater range than other types of firearms and have greater destructive potential, but also suffer the inaccuracy inherent in any indirect fire weapon (when used in such a capacity). Furthermore, ammunition is always of limited quantity.


Most modern shells are cased despite the added complexity and weight. A cased cartridge consists of a projectile (in this case, a shell) blocking the throat of a metal sleeve, trapping the propellant inside. The bottom of the case is closed and features a primer which, when ignited, also ignites the propellant. The rapid expansion of gases forces the shell free from the case and accelerates it down the barrel. The primer can be ignited by either an electric charge or percussion. Typically, only gas guns utilize caseless shells.