HuntingNet.com Forums - View Single Post - Bullet density and Ballistic Coefficients
Old 11-16-2009, 06:12 PM
  #8  
Scott Gags
Typical Buck
 
Join Date: Jun 2005
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Originally Posted by Big Z
Thanks mike,
However, I'm still not getting anything related to the flight characteristics of 2 different bullets made of materials with differing densities.

Here's a scenario that might help understand the question. Let's assume that we have 2 bullets. One made of lead, one made of copper. They are formed in the same mold, loaded in the same rifle and shot at the same speed. What is the difference? Surely there is something, beyond what a calculator using BC and velocity tells us.
If the bullets have the same shape the heavier bullet will have a higher BC. The formula is as follows:

BC=SD/Form Factor

BC is Ballistic Coefficient
SD is Sectional Density
Form Factor is a representation of the shape

Since the Form Factor is the same in your example the only variable is SD. So the BC is directly affected by the SD and if the SD goes up by 10% so does the BC go up by 10%.

I believe a lead bullet is 27% denser than copper so a lead bullet of the same shape will have a 27% higher BC.
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