Rate of fire
![](http://upload.wikimedia.org/wikipedia/commons/thumb/1/18/M61_Vulcan_on_pedestal.gif/220px-M61_Vulcan_on_pedestal.gif)
Rate of fire is how fast a weapon can fire or launch its projectiles. It is usually measured in rounds per minute (RPM or round/min), or per second (RPS or round/s). Pistols usually have a very slow RPM, which large machine guns may get up to 1000 RPM. The M61 Vulcan, a gatling-gun, could fire around 6000 RPM in tests.