The number you enter in the adjustable parameter box will be how long your trigger is pressed, and for how long the trigger is released before the rapidfire combo is reset. If you wish to fire faster you will use a lower number, if you wish to fire slower you will use a higher number. It is always important to remember that most games will limit the amount of shots you are able to fire within a certain amount of time, so setting the RapidFire speed too fast will work against you and slow the weapon down.
This video will explain how to set the Adjustable Rapid Fire parameter to get the fastest firing speed for your weapons. While I used the Black Ops 3 Gamepack for this video, the mod works the same throughout every Gamepack.
