There's a real danger in making assumptions about how a pellet will perform based solely on ballistic calculations and a BC figure you got off of a spreadsheet somewhere. The real world is often very different from the calculations. (not necessarily because the calculations are wrong, it's usually a case of the inputs to the calculation were wrong to start with).
Does anyone know where these BC figures come from?
Chairgun has JSB Heavies listed with a BC of 0.031 but where did that number come from?
It's not from the manufacturers, so where does it come from and what process was used to come up with it and also what is it? Is it an average? What was the sample size? What was the standard deviation?