How do extremely low accuracy levels work?

With Gaige's Anarchy skill it's entirely possible to gain a -100% or greater accuracy penalty. Borderlands' accuracy was always sort of funny so 0% accuracy (which I think was possible with Sledge's Shotgun) didn't quite mean "your bullets can literally go anywhere".

So in Borderlands 2 what happens with extremely low accuracy values, below 0%? Does it bottom out at 0%? What exactly does 0% accuracy mean in this case?

Solution 1:

Quoted From Borderlands Wiki http://borderlands.wikia.com/wiki/Stat_modifiers

Negative totals

When the total is negative, borderlands uses another formula. Instead of directly applying the modifier, Borderlands applies it to a reciprocal function. For example, for a gun with a spread modifier of -130% from a barrel5, the modifier will be of 1/(1 + 1.3); if that gun had a base spread of 2, the final spread would be 0.87.

The rationale for this mechanic is to have the same scale of effect, regardless of the modifier's sign.

A notable list of stats that are affected by this rule are:

-Damage: Many weapon parts actually have negative bonuses.
-Spread: Very often breaks the -100% bar.
-Damage reduction: Brick's Juggernaut skill; Lilith's Silent Resolve and Resilience skills; Roland's Grit skill.
    -50% Damage Reduction => Player takes 66% Damage
    -100% Damage => Player takes 50% Damage 
-Recoil: Internally, the game uses a "Recoil" stat, which it displays as its inverse, "Recoil Reduction"

So I think it will be same for borderlands 2 :)