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Originally Posted by Salavee
True enough, but the bullet with the higher BC will also have the higher SD. Sectional density and form factor are major components of the formula used to determine BC. Check it out.
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Not necessarily. Higher BC doesn't necessarily mean higher SD. See your comment below. The .308" 180gr RN, SST, and SP all have identical SD figures. The difference between them is in their respective form factors/drag coefficients, leading to vastly different BC values.
Quote:
Originally Posted by Salavee
Yes it would, remembering that the SST bullet has a much better form factor than a .308 RN, so not really a fair comparison.
Form Factor at work again. Try those numbers with the same bullet design.
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WRT your comments about controlled-expansion bullets versus C&C bullets with a high SD, I'd beg to differ. I think most experienced hunters would agree that a .308" 165gr Partition will routinely penetrate deeper and perform more reliably than a standard 180gr C&C bullet like the Sierra PH or the Hornady SP, despite have a lower SD value. And "controlled expansion" refers to bullets designed to limit expansion, which does not include bullets like the Sierra PH and Speer SP, etc. It usually refers to bonding, a partition, mono construction, etc.
Quote:
Originally Posted by Salavee
Again, with bullets of the same weight and design, the one with the higher SD wins.
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Again, not necessarily. A 140gr TTSX/PT/AB kills better when fired from a 7-08 than a 175gr bullet of similar construction. When you have controlled expansion ensuring good penetration, tissue damage is increased significantly by higher impact velocity, SD notwithstanding.