Originally posted by Charlie Lamb: The Hoyt rest is a very forgiving rest so it's not surprising that you would experience different tuning results "off the shelf".The difference you see shooting off the shelf may be an indication of why you are wearing out the Hoyt rests. The rests are "absorbing" the contortions of the slightly stiff arrows. Find the correct spine and you'll not only get better tune off the shelf, but you'll also get better life from the Hoyt rests with the possibility of improved accuracy.