Re: questions about bullet weight vs twist ratio
You are right, this does go against convention wisdom, but then again the author applies fairly sophisticated formulas that take into account a lot more than just length and bullet weight. Size, velocity, shape, air density, etc. I think the practical aspect to the charts shown in the book is that if the twist rate exhibits a stability factor of at least 1.4, it is likely to be stabile. From the data shown, some bullet designs must be better than others irrespective of weight and length.
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