Despite claims floating around the internet to the contrary, paintball guns can rarely shoot above 20 balls per second. Paintball guns are able to cycle (fire without any paintballs) much faster, but the limiting rate of extremely fast paintball guns is how fast paintballs can be fed into the chamber and most hoppers can’t reliably load faster than the about 20 bps.
In terms of guns specifically built to shoot fast, the fastest video I have seen is of a gun shooting with a spring-loaded Q-loader where the authors claim 34.5 balls per second. While I’m not sure if their numbers are accurate, there is no doubt that the gun is shooting very fast.
In general, remember that claims of balls per second are only able to be achieved during controlled tests. In actual games, it is very rare to see a player who is able to shoot above 20bps (even with ramping) and many games cap rates of fire to even lower rates. For semi-auto only games, most players can’t (and have no need to) maintain a rate of fire above 15 bps.
