JSB King Heavy .25 ballistic coefficient?

While it is accepted that BC is a function of mass, diameter and drag coefficient there are many, many factors that need to be taken into account. The type of barrel, diameter, riffling, interior roughness value, temperature, humidity, altitude and on and on and on. I've had two TX200 MkIII air rifles. The first being stolen in Phoenix. Each rifle had a slightly different BC using the .22 H&N Baracuda Green pellets. Each rifle was tested under the same environmental conditions at the same facility. The first TX had a BC of 0.0135 while the second had a BC of 0.0137. This slight change did not effect the POI, however, it did effect retained energy. 0.0135 = 90% at 6yds, 80% at 13yds, 70% at 20yds, and 60% at 29yds. 0.0137 = 90% at 6yds, 80% at 13yds, 70% at 21yds, and 60% at 30yds.
 
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BC is always changing and some ballistic programs allow you to enter multiple BC'S for extremely precise data and shooting at multiple ranges. Most airgunners don't need to take it to that level and can get what they need from one general bc. Gamy rick points out this and it is up to the end user to decide how deep they are going to take there shooting. In most cases, even an averaged BC works well for general 100 yard and under shooting. Things surely get more critical as distance increases!!