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Varmint Hunting
.20 cal barrel recommendations
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<blockquote data-quote="Hugnot" data-source="post: 2794556" data-attributes="member: 115658"><p>Miller Stability Estimates for .204 bullets, 40 H VMax, 39 Sierra Blitz King, & 40 Berger HpBt:</p><p></p><p>The Miller Twist Calculator, an estimator, is used by JBM & Berger for determining twist rates needed for adequate stability - Sg. The math is involved but not rocket science. An adequate Sg value should not be less than 1.4. Environmental factors affecting bullet stability are temperature and barometric pressure. Barometric pressure will vary with altitude - higher is lower. Humidity affects barometric pressure as the hydrogen molecules in water vapor are lighter than nitrogen molecules - humid is lower pressure.</p><p></p><p>[ATTACH=full]454630[/ATTACH]</p><p></p><p>My 11 twist works real good on warm days at 3000 plus feet on pop can size rodents but what if some other bullet like the 40 Berger was needed for shots on bigger targets on cold days - 11 twist Sg 1.26, 10 twist Sg 1.53.</p></blockquote><p></p>
[QUOTE="Hugnot, post: 2794556, member: 115658"] Miller Stability Estimates for .204 bullets, 40 H VMax, 39 Sierra Blitz King, & 40 Berger HpBt: The Miller Twist Calculator, an estimator, is used by JBM & Berger for determining twist rates needed for adequate stability - Sg. The math is involved but not rocket science. An adequate Sg value should not be less than 1.4. Environmental factors affecting bullet stability are temperature and barometric pressure. Barometric pressure will vary with altitude - higher is lower. Humidity affects barometric pressure as the hydrogen molecules in water vapor are lighter than nitrogen molecules - humid is lower pressure. [ATTACH type="full" alt="Screenshot (617).png"]454630[/ATTACH] My 11 twist works real good on warm days at 3000 plus feet on pop can size rodents but what if some other bullet like the 40 Berger was needed for shots on bigger targets on cold days - 11 twist Sg 1.26, 10 twist Sg 1.53. [/QUOTE]
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.20 cal barrel recommendations
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