Grooving definitely works in my experience, although I get the same effect with 2 or 3 grooves spaced evenly from the point to the front edge of fletching. For plains NA arrows, cutting the self nock at the base of the shoot not only facilitates an authentic, flared nock but also makes grooving the entire shaft length largely unnecessary. Most plains NA arrows have 2 or 3 grooves - either straight, wavy, or a combination - running from the point or just behind the point binding to the front fletching edge. The bases of dogwood shoots are usually fairly straight, while as the shoots grow the small offshoots can cause kinks. Grooving this area is the most important. The key is to roughly straighten the shafts, then groove them, then grease and heat them for final straightening. This creates the small, hardened ridges along the grooves that inhibit warping.
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