A reloading press is a tool that allows the user to refurbish and reload spent bullets. Along with a series of specialized dies for each ammunition type, a reloading press can reshape spent casings, re-attach primers, refill them with powder, re-mount a bullet and crimp the round closed.
When a bullet is fired, the primer explodes, the powder burns and the bullet fires. The casing may be deformed by the explosion, but it is otherwise reusable. Hand-loading ammunition can save sport shooters a substantial amount of money over purchasing new bullets for full price. However, each casing can only be reused a certain number of times before the repeated wear and tear makes it too dangerous to use.
Reloading presses come in many different varieties. The cheapest ones are entirely manual, and require the user to switch out dies in between stages of reloading. Turret-style or progressive presses allow the bullets to move through various "stations," first being reshaped by one die, then re-primered by a second, and so on. Every time the user pulls the lever, each die performs its task, and then the bullets are cycled ahead to the next station. In conjunction with automatic feeders for casings, primers and powder, these presses can greatly reduce the amount of time it takes to reload ammunition.