Loaders
Loaders, commonly known as hoppers, hold paintballs for the marker to fire. The main types are gravity feed, agitating and force-feed. Stick feeds are also used to hold paintballs, although they are not considered to be "hoppers".
While agitating and force-feed hoppers facilitate a higher rate of fire, they are subject to battery failure, as well as degradation if they come into contact with moisture. Such hoppers which are not fitted with photoreceptors are prone to problems with ball breaks. When a paintball leaks paint into the hopper from a break in the hopper, the gelatin shells of the paintballs can deteriorate, causing them to stick together as well as jam in the barrel.
Read more about this topic: Paintball Marker