Ballistic coefficient of jsb king heavys.

[Aparks454]

Hello AGN,



I was trying to put some new data in my ballistic calculator last night and have always taken for granted when reloading for my powder burners that the ballistic coefficient is noted in the reloading manuals. Also to come up with one using AOA’s calculator you need a muzzle velocity and a velocity at the target. Does anyone have a base line or generic one to use? I’m shooting the .25cal 33.39 grain jsb king heavy. Also I’m not super educated on the subject of ballistic coefficient so it may be something you have to calculate on your own using a chronograph. Any input will be much appreciated.

 

[mtnGhost]

They were in the 0.036-0.038 range with the RAW that I had (muzzle to 10y calculation).

 

[18.13]

http://hardairmagazine.com/ballistic-coefficients/

 

[Steamer]

With my RAW Hi-Power .25 using JSB 33.95 the BC is .0486. Average muzzle 920 ftps and 788 at 50 yards. I used ChairGun calculator (it's more accurate than AOA). This is consistent Hardiar Magazine's BC chart.

 

[bdzjlz]

StrelokPro calculates through BC with this pellet from my RAW at .050.

 

[Aparks454]

Thanks for all the great info everyone. Member 18.13 this is exactly what I was looking for. Thanks again.

 

[O2bmark]

Starting at~ 885fps and ending at 60 yards using LabRadar data I get between .051-.054 using Chairgun. I've been using .052 for over a year now and it tracks pretty well but I'm shooting no more than 120yds. I haven't used labradar on this .25 pellet past 64 yards and don't know how far downrange I can actually track it. Further data would be helpful. 

 

[JWilson]

The BC of a pellet changes with velocity. I use the multi-BC function in Strelock. It takes some time, but once set up it tracks very well. I just started using this function in the last couple months but find it more accurate than using an average BC.