If you have three different models for subsonic, transonic, and supersonic, then you have three different BC's.... All I'm trying to do is come up with a model that is an improvement over what we have now, and still covers all three velocity ranges.... Maybe I'm completely wasting my time.... but then on the other hand, it's my time to waste.... Perhaps the real waste of time is trying to share?.... Bob
My personal opinion is that most of the barrels we use have too high a twist rate for diabolo pellets, causing Dynamic Instability and spiraling as we push the velocity....The skirt certainly has two functions, drag stability and bore sealing at the relatively low pressure we see compared to a PB.... I am not aware of a good reference on the twist rate of airgun barrels, although certainly there is information available on individual ones....Bob