You should also find the right spine arrow for the specs--bow weight, arrow length, tip weight, etc. Any good archery shop should be able to help with that. He would need this info and the fact that you intend to shoot with fingers. A shop might also have some arrows made up that you can try different ones to see what appears to fly the best. It would get you in the ballpark.
If You're Not Living on the Edge You're Taking Up Too Much Space
Martin/Rytera Staff Shooter
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