Reply To: Is Ballistic Coefficient a Constant?

Forums Pellets, Projectiles, Slugs, & Ammo Is Ballistic Coefficient a Constant? Reply To: Is Ballistic Coefficient a Constant?

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mmahoney
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Thanks for that link, 18.13. I copied this from the link you shared.

So if the BC of a projectile varies because of different amounts of drag at different velocities, which number gets reported as "the" ballisitic coefficient? The max? The mean?

I know there are different models that are used to approximate this affect of drag at different velocities….GA, GU, G1 etc., but always thought that the ballistic coefficient was the coefficient and the drag was a different variable.

For example, when shooting at 5000 ft my pellet experiences less drag than at sea level. If I shot the pellet underwater, it would have significanlty more drag. A good trajectory calculation would need to include the fact that the environment is different but not that the pellet is. Am I wrong when I assume that the drag law (GA for example) is supposed to take into account the environmental differences instead of the ballistic coefficient?

I guess I'm still trying to get my head around why the darn number isn't called the ballisitic variable instead of the ballistic coefficient.