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)