Greenhill Formula
Definition
Alfred Greenhill's 1879 empirical formula for the minimum barrel-twist rate to gyroscopically stabilise a bullet of given length and calibre. Uses a single constant (150 for lead-core bullets). Reliable for blunt ogive projectiles; less accurate for modern spitzer bullets.
Related terms
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- IBHVG2
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- LabRadar
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- Le Duc Model
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- Oehler Model 35P
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- PRODAS
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Explained in
- Internal Ballistics: Muzzle Velocity Prediction ModelsAlfred Greenhill's 1879 empirical formula for the minimum barrel-twist rate to gyroscopically stabilise a bullet of given length and calibre. Uses a single con...