Re: Wind Drift
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as bullet weight increases, so does bc.
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This is not always so. Ballistic coefficient is derived from the coefficient of form which means that the bullet's shape is the important thing and weight is indirectly related. Usually, as you add weight to a bullet it gets longer. But the shape must still be aerodynamic or the added weight is counterproductive because velocity will be reduced and time of flight will increase. If weight is added to a bullet and the shape remains the same, then the bc will go up because the bullet is getting longer while the shape is staying the same.
Take for instance the 160 grain 6.5 mm round nose Hornady flat base. BC=pathetic (I believe it is in the .3's) and then look at the 140 grain Berger VLD with it's bc of .627. Almost double the bc with 20 grains less weight. Why? The coefficient of form or the shape is much more aerodynamic on the Berger.
I realize you probably already know this, but it helps to clarify the exact derivitive of the definition so as to not confuse the original poster. [img]/ubbthreads/images/graemlins/wink.gif[/img]
If it's not far, it's boring.