You got better arrow flight because you increased the spine by reducing the arrow weight. The reduction in weight has little if anything to do with arrow flight, except for reducing the spine. An arrow that is matched to the bow re spine will fly well regardless of its weight, though for heavier arrows one generally needs to increase the spine a little. You just hadn't found it with your initial set up. But you appear to have it now.
I wouldn't put too much stock in the increase in kinetic energy. The kinetic energy formula is biased toward arrow speed. A better measure of an arrow's penetration potential is momentum, and that formula is more biased toward arrow weight. Here's an example, if one could, throw a ping pong ball against the wall at 100 feet per second, and a lead ball of the same size at 50 feet per second, which one will penetrate the most? The ping pong ball likely has has more kinetic energy, the lead ball more momentum. This is an oversimplification, of course, but pretty much describes the difference between the two formulas.
As long as I'm on my soap box, I might as well offer one other observation. Kinetic energy is a very popular concept among compound shooters and their 300fps bows. Since most pro shops deal almost exclusively with compound shooters, that's the language they talk. Most traditional bowhunters, on the other hand, are more concerned with momentum/penetration.
Glad your current set up is working for you.
Topic: I Learned a couple things today. (Read 731 times)
