Well there are a few things you can try
Leveling your mouse pointer to chests and short bursting/1 tapping
Lowering or raising your mouse sen ingame to a comfortable level
Spraying only in close range
Lastly finding a weapon to best suit your play style i.e M4 for mid to long range/AK for short to mid
>The mouse precision option I think is used for taking away the 'smooth moving' while using your mouse. So I think it wouldn't affect you at all ingame.
Hope it helps