Do Bullets Go To Sleep?
Previous experiments using widely accessible equipment that attempted to quantify damping of pitch and yaw were focused around a decrease in ballistic coefficients, not drag coefficients. The experiment reported here was carefully designed to eliminate as many confounding factors as possible to increase confidence in the results. To our knowledge, this is the first published data using optical chronographs in support of the theoretical prediction of reduced drag as pitch and yaw are damped out. This experimental design is expected to be useful in distinguishing between deviations from a given drag model due to the shape of a bullet and increases in drag due to pitch and yaw and should be useful in a wide variety of situations where experimenters desire to detect pitch and yaw in a given combination of bullet and rifle. Of course, introducing fourth and/or fifth chronographs to extend the technique to possible third and fourth 50 yard intervals has the potential both to better quantify the range over which pitch damping is occurring, as well as give greater certainty to the results.
This research was funded by BTG Research (www.btgresearch.org) and the United States Air Force Academy. The authors appreciate the use of Dragonman's range.
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Alex Halloran, Colton Huntsman, Chad Demers, Michael Courtney, “More Inaccurate Specifications of Ballistic Coefficients,” 2012, http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA555975
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