Loaders
Loaders, commonly known as hoppers, hold paintballs for the marker to fire. There are many variations, but the primary types are gravity feed, agitating, and force-feed. Stick feeds are also a means to hold paintballs, though they are not, strictly speaking, considered "hoppers".

While agitating and force-feed hoppers facilitate a higher rate of fire, they can fail due to dead batteries as well as contact with moisture, which keeps many woodsball and scenario players away from them. Ball breaks pose a problem for all hoppers, regardless of design. When a paintball leaks paint into the hopper from a break in the hopper, it can cause the gelatin shells of the paintballs to deteriorate and sometimes stick together.
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