Bare shafting wood isn't always worth it imo. When I've done it I end up with spine ratings about 20# more than my draw weight. It works, but I end up with an arrow that is around 12 gpp. I like a flatter trajectory so 10 gpp is better for me, but that means a shaft that shows pretty weak when bareshafted. I compensate by with 5" fletching, usually 4x90. I know a lot of folks here will say I'm nuts, but I get great bh flight. Besides, that's the whole point of fletching, right? Now, if I shot carbon, I would definitely bareshaft. I guess my point is that you dont need perfect results when you bareshaft that test pack, just get in the ball park. If shafts are breaking on oblique impact with the target, you're too weak. If not, you're darn close.