RE: Best placement for an arrow?
Forget the mechanicals when it comes to hunting hogs.
Get that bow tuned first of all.
Poor arrow flight equates to poor shot placement, poor penetration, and lost game. If your arrow is reacting unpredictably at thirty yards, it is doing the same thing at 20. You may be hitting relatively close to where you aim, but the arrow wants to do something else.
Mechanical broadheads are not the fix to a poorly tuned bow.
Spend the necessary time to tune your rig and pick a fixed blade broadhead to hunt with.