Topic: 2009-06-04 range test data
I did some tests in 2009 to help determine the drag coefficient of a Nerf dart (Slugs, specifically). Back then I said 0.34 was a good approximation, but now I think something lower like 0.15 is right based on wind tunnel tests Split did and my more recent analytical external ballistic work.
mass (g) range (ft) muzzle velocity (ft/s) 1.05 84 186.4 1.09 74 170.0 1.08 81 180.5 1.01 88 200.0 1.11 88 184.8 1.15 104 186.9 1.11 79 183.8 1.05 83 195.9 1.00 80 203.8 1.00 81 205.6
The gun was fired flat (or at least as flat as I could hold it). These shots were fired outdoors. As I recall, I tried to avoid wind, but surely wind did affect these results. I think the 104 foot shot was greatly helped by wind as that range is about where the dart would land without drag.
Take what you want to from these tests. I wish I had done more; perhaps I will!
Edit: Beaver's more recent tests used a level to ensure the gun was shot flat. The drag coefficient from this data has an average of 0.67 and a standard deviation of 0.16. Beaver suggested that firing flat felt like firing down, so the apparently low drag coefficient actually was caused by shooting with a small angle up.
Last edited by btrettel (2012-03-21 13:10:01)