.25 JSB BC + Cricket testing

[mcoulter]

Just logging what I found when shooting today (40f, 1300 alt)

JSB King MKII Heavy 33.39 from my .25 Cricket:

MV = 850 fps 
V2 = 735 fps @ 53 yards
BC = 0.0519 as calculated through Chairgun Pro.

HardAir Mag came up with a BC of 0.046 at a MV of 200 fps less. (https://hardairmagazine.com/ballistic-coefficients/)



These results below were from a previous session with a slightly different tune on the cricket but similar temps and same location:

JSB Kings 25.39 from my .25 Cricket:

MV = 900 fps 
V2 = 730 fps @ 53 yards
BC = 0.0380 as calculated through Chairgun Pro.

HardAir Mag came up with a BC of 0.038 at a MV of 130 fps less. (https://hardairmagazine.com/ballistic-coefficients/)

Chrony = ProChrono

 

[vmaxpro]

Very very close to what I came up with too. What I find strange is I got a better bc with the 34 gr at 970fps than I did at 850 fps. Usually its worse, maybe I did something wrong?

 

[JungleShooter]

Thanks for sharing your BC test results!

This is helpful, esp. at different velocities.  

Matthias

 

[mcoulter]

Very very close to what I came up with too. What I find strange is I got a better bc with the 34 gr at 970fps than I did at 850 fps. Usually its worse, maybe I did something wrong?

I'm definitely a novice when it comes to this, but maybe you can share how you tested your BC and folks can chime in!

And Matthias, I'm glad you found this helpful!