I'm modifying the assault rifle's accuracy - as I understand it - but there are five distinct stats to its three modes' Scatter Parameters, at least one of which I don't really grasp the meaning of. I'm just going to put all five below with what I'm guessing each means, in case I'm wrong about more than one of them.

Scatter parameters

• Scatter distance: Maybe something like the amount each shot reduces accuracy for the next one? If so, not sure what units are used here.
  
• Scatter radius min: The closest the projectile can hit to the center of the crosshair, in degrees
  
• Scatter radius max: The farthest the the projectile can stray from the center of the crosshair, in degrees
  
• Scatter Y stretch: A multiplication (or division with a negative number) of the previous two numbers to simulate more (or less) vertical recoil than horizontal.
  
• Scatter Y add: As previous, but addition (subtraction with negative number) instead.

(Edit: Ryason55's post below corrects the strikethrough lines above.)