This is a modern cartridge: 

1.  the bullet/projectile

2.  the case; holds all parts together

3.  the propellant (ie: gunpowder)

4.  the rim; a place to grip the casing to remove it from the chamber once fired

5.  the primer; ignites the propellant

     Between 1854 and 1857 Sir Joseph Whitworth conducted a series of rifle experiments and proved the advantages of an elongated bullet. In 1882 Major Eduard Rubin invented the copper jacketed bullet - and elongated bullet with a lead core in a copper jacket. The surface of lead bullets fired at a high velocity may melt due to hot gases behind the bullet. Because copper has a higher melting point and hardness, copper jacketed bullets allow greater muzzle velocities.