RE: HOW DO YOU DETERMINE WHAT GRAIN OF BROAD HEAD TO USE.
I mainly look at arrow weight and FOC. My finished arrow is around 440 gr with an FOC of 9.7. This gives me very good BH flight. Just play around and you will find what works. I also wanted a bit heavier weight for hunting, so I went with the 125 gr head, Magnus Stinger to be exact.
JMAC