I figure speed can vary person to person. Isn't it when the arrow is traveling through the centre of the bow you get the most performance? IMO shooting release. What if that person or person's have bad form then the ocilation of the bow from torque, or string can cause slower results. Also, differences in arrow make up, aluminum vs carbon. Even @ the same weights and spine, the carbon will travel faster then the aluminum. Why? because its very simple engineering the straighter the line of travel the faster the exelleration and probably top speed. While the aluminum arrow's tail is kicking out its most definetly losing speed and the carbon's straighter flight affords it more speed. Like Len has said, relative issue. Im not a super physics genius, but its easy to see differences that may cause speed variances. I shoot arrows from my recurve, maybe going 180-190's area. When I shoot a bow doing 230 or even 250 its like greased lightning to me, geez I can't imagine myself shooting 270's-80's. I just figured I would throw in my few small change, thoughts. Good shooting all.
Dylan

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