A method of manufacturing ammunition 10 for firing from the barrel of a weapon comprises forming a mould 32 having an interior surface, placing a core 42 in the mould 32 to produce a casting void 43 and pouring a liquefied solidifiable material into the casting void 43. Upon solidification of the material, the core 42 is removed to produce a projectile body 12 having a closed end and an opposite end. The removal of the core 42 also creates the cavity 18 in the projectile body 12 that opens onto the opposite end. The projectile body 12 is removed from the mould 32 and a quantity of propellant 22 is deposited into the cavity 18 through the opposite end. A seal 26 which incorporates a primer is pressed into the opposite end. Circumferential flanges 30a and 30b are integrally moulded with the projectile body 12.