Projectiles with sealed propellant are described herein. In one embodiment of the invention, a projectile includes a chamber having a propellant charger, an exit from the chamber for release of propellant gases into a barrel when the propellant is ignited to fire the projectile, and a seal to block the exit which is opened by ignition of the propellant within the chamber but is resistant to ignition of other propellant in the barrel, where the seal is carried from the barrel by the projectile after the ignition. Other methods and apparatuses are also described.