Editing Projectile (section)

==Motive force==
{{See also|Projectile motion}}
[[File:Schwerer Gustav projectile 2.jpg|thumb|right|220px|Projectile and cartridge case for the huge [[World War II]] ''[[Schwerer Gustav]]'' artillery piece.  Most projectile weapons use the compression or expansion of gases as their motive force.]]

[[Blowgun]]s and [[pneumatic rifle]]s use compressed gases, while most other [[gun]]s and [[cannon]]s utilize expanding gases liberated by sudden chemical reactions by [[propellant]]s like [[smokeless powder]]. [[Light-gas gun]]s use a combination of these mechanisms.

[[Railgun]]s utilize electromagnetic fields to provide acceleration along the entire length of the device, greatly increasing the [[muzzle velocity]].

Some projectiles provide [[propulsion]] during flight by means of a [[rocket engine]] or [[jet engine]]. In military terminology, a [[rocket]] is unguided, while a [[missile]] is [[guided missile|guided]]. Note the two meanings of "rocket" (weapon and engine): an [[Intercontinental ballistic missile|ICBM]] is a guided missile with a rocket engine.

An explosion, whether or not by a weapon, causes the debris to act as multiple high velocity projectiles. An explosive weapon or device may also be designed to produce many high velocity projectiles by the break-up of its casing; these are correctly termed ''[[Fragmentation (weaponry)|fragments]]''.