When you open his skill tree you might need to open up the tree in an offline poe builder, not sure if its fixed.
Keeping in mind that you can tweak how much HP you take and instead take more damage nodes.
The main thing is to have Drillneck + Pierce Gem + Pierce nodes to hit 100% pierce chance.
Frenzy until stacks are maxed, CA until dead.
I am nervous about how long Empower is going to take to level as it does nothing at level 1.
That's why I choose the +1 to gems over the +2 to bow skills. Empower gets level 2 from the get go and you get the +2 on CA.