I discovered this interesting site while I was at Mac's Praire Wings, while I was in Stuttgart, Ar.Thesite is very interesting tell you just about any thing you need to know your correctspine, arrow speed, Ke, arrow mph an Ke at any yardage. Do not know how accurate, but it described my bow to the T. If, you already know about this, well I have not told you anything.It even hasa print out that you can set your pins up with an they say it is accurate.

Just go to
"archers advantage"

The only problem you have to purchase it or go to MPW in stuttgart,Ar.