I spent the day measuring the Ballistics Coefficients of all the .25 cal. pellets I have.... I used my Hayabusa, set up for about 960 fps with JSB Kings.... I shot 5 shots groups inside with the Chrony at 1 yard from the muzzle.... I made sure the tank pressure stayed between 2000-3000 psi for all strings, which is 100 psi above the regulator setpoint of 1900.... I then repeated all the strings outside with the Chrony at 25 yards from the muzzle.... and I even shot all the strings at the same part of the tank fill as I did the first time to be as consistent as possible.... The BCs were then calculated using ChairGunPro.... Here are the results.... Remember that these BCs are only valid for this particular rifle at the velocities specified.... although they should be a good indicator of what to expect....



Here are a few comments.... The JSB Kings had the highest remaining Velocity at 25 yards, and the tightest Standard Deviation at that distance.... I was a bit disappointed in the BC of only 0.024, but then I thought about how fast they are being driven, and it's very possible (in fact probable) they are beyond the sweet spot of the BC curve at 960 fps.... The H&N Baracudas (aka Beeman Kodiaks) had the highest BC at this power level.... The maximum Energy went to the EunJin Pointed pellets, both at the muzzle and at 25 yards.... but of course they had the lowest velocity as well....

As far as I'm concerned, a .25 cal is all about power and range.... Based on that, I'm only going to test those pellets which had over the 36.2 average FPE remaining at 25 yards for accuracy.... That means only those eight pellets with a BC of over 0.018.... Those that show promising accuracy will then get more work to determine the velocity where the BC peaks.... I'll keep you posted on further testing....

Bob