Ok so there is all these different grains on broadheads. my question is what exactly does (grain) mean? meaning what is the diff and what does it do ? i know it is the weight but do you want a heavier weight or a lighter one?
The weight of the tip is determined when deciding what DW you want to shoot and when building the arrow. The tip weight will affect your dynamic spine so you want the correct weight. I have one arrow(.300 spine) with a 100gr insert and a 200gr tip (300gr tip weight) that I shoot at around 67#'s. I got a new bow that shoots faster and I want to take that same shaft and insert yet switch the BH from 200gr to 100gr which will give me a 200gr total tip weight. Lowering the BH weight effectively stiffens my dynamic spine so that the faster bow can shoot the same shaft configuration. I will likely have to lower the DW on the new bow to somewhere around 65 but that is what I wanted to do anyway. I am also going to make this same shaft with a stock 22gr insert and a 125gr tip and see what the new bow does with that. I likely will be back up to 70#'s DW for that configuration. So, to answer your question: You want a heavier or lighter tip with regards to how the bow is setup and how the arrow is setup and the lighter/heavier tip will help give you the correct setup for proper transfer of energy from bow to arrow and proper arrow flight. Grain is an ancient measure of weight I think is related to wheat or something like that.
