Many people don't realize that you mightneed to tune mechanicals as well. I was shooting a two blade mechanical w/ a 2" cut at my foam target and the arrows kept sailing on me. When I went to my fixed blades, they flew great. Don't assume that just because you have a mechanical they will fly like your field tips. Practice with them just in case. I'm glad I did or I would have missed a buck. Even mechanicals have blades that slightly portrude and when you are shooting todays high speed bows anything can happen when you introduce aerodynamics. Practice Practice and Practice some more....