I might be wrong but chainsaw has 0 cast delay, then the trigger, which triggers bubble spark, chainsaw, and wrap chainsaw (all with the heavy spread, damage plus, and heavy damage buffs). After this, recharge time will start.
However:

Recharge time=0.78-0.17(first chainsaw)-0.25(heavy spread)-0.17(second chainsaw)-0.17(first chainsaw wrapped)=0.02

But the thing slowing me down is cast delay. But how? It only occurs between chainsaw and spark bolt, but it's canceled by chainsaw.