which may be of some interest to those who didn't see it before.

Shot with one rifle and one pellet type JSB Exact 15.9 gr.

The 40 shots are rank ordered according to near range velocity. Each shot shows near range velocity at 6 ft and far range velocity at 36 ft and the BC for that individual shot.

The right side column shows mean near range velocity, average Mach number and average BC for each ten shots according to their ranked number

(not the order of shooting) and so are random in terms of possible environmental changes.

Errata: the # 4 shot from the top should read BC .0254

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It can be seen that there is a trend for BC to go up as near range velocity goes down. It should be noted that muzzle velocity would be some 6+ fps faster than at near range. The velocity range brackets the velocity of 875 fps to 880 fps favored by many shooters as being a desirable velocity for precision shooting. ......... Kind regards, Yrrah.

Thanks a lot, Harry, for running this test. Finally, some data to chew on instead of rumor and conjecture.

BC changes much more than I would have guessed. So, the diabolo pellet is slipperier at low velocities.

This also debunks the theory that the BC of a pellet changes drastically with the gun. It doesn't. It changes with the velocity, even if in the same gun. Granted, there are other factors at play including obturation, but these would seem to be minor in comparison to what Harry has found.