Bullet weight and B.C.

[Alex Wheeler]

How much does bullet weight effect bc? Example 2 bullets with identical shape, one weights .2 grains more. How much does that effect the bc number? I am not familiar with the formulas used in figuring bc.
Thanks
Alex

 

[Alex Wheeler]

I looked in my Litz book and found the formula. Ran the numbers for the 105 vld at 3000 fps. .2 grains changes the bc by .001 which works out to be .36" at 1k. So if your bullets vary 1 grain your adding 1.8" of vertical at 1k!

 

[Turbulent Turtle]

And you adjusted the MV to account for the heavier bullet, right?

 

[mikecr]

My calcs agree with zfastmalibu, and bayou has a good point in that it could matter less when the rubber hits the road.

 

[Alex Wheeler]

And you adjusted the MV to account for the heavier bullet, right?

Thanks for reminding me to do that. 1 grain slows the bullet 8 fps, but ups the bc .005 for a whopping .030" difference at 1k,