NJB,
Did you papertest your bow? It can tell you of any tuneup problems.
The first thing I would think is a spine problem. Thats the most common tuneup problem. Is this fingers or release? Best way to tell if its a spine problem is to turn the bow down 2-3 turns. (If you have the space to do so.) Going to a larger broadhead will not help if its a spine and its effects on trajectory will be negative.
Usually the problem is one of either porpoising or fishtailing. This can be adjusted with the nocking point and/or arrow rest.
Lastly it could be a clearance problem. If the above doesn't fix this then spray the veins down with foot powder and shoot it. If it contacts something you will know where.
Two things for you. They will help you fix the problem and be resources for the future.
1. go to the Easton website and use the free download of the
Arrow Tuning and Maintenance Guide.
2. Ragsdale's Q&A is about the best thing I know of online for this
http://domino.htcomp.net/ragsdale.ns...nt=30&Expand=2
Yes this will affect accuracy. Also important is the energy loss you experience. Hope this helps.
Arrows are "corkscrewing" - Help!
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