RE: how light is too light.
I am shooting a 27.5" Carbon express maxima,and a 100gr tip.Total weight 375 gr.I mad a complete pass through on a doe.My bow is set at 70lbs,so that is 5.3 grs per pound.Alot of people would say that is way too light,but it is 72ft lbs of KE.And slammed an additional 8" into the ground.So how could that be too light?Personally I would not go under 375 with a 70lb,or 350gr with a 60lb bow.Alsoa sharp broadheadwill make a huge difference.If it's not cutting it's going to lose penetration fast,no matter how heavy the arrow is.Hope I helped.