Le Duc Model
Definition
An empirical algebraic formula (1873) relating muzzle velocity to peak chamber pressure via two calibration constants. Produces velocity estimates within 3-5% of measured values when calibrated against test-fire data; 8-12% without calibration.
- Type
- Empirical algebraic formula
- Year introduced
- 1873
- Relates
- Muzzle velocity to peak chamber pressure
- Accuracy, calibrated
- Within 3-5% of measured values
Common questions
Why does accuracy depend so much on calibration?+
The model uses two constants fitted to a particular cartridge and barrel combination. Calibrated against real test-fire data those constants absorb the specific propellant and barrel behaviour, giving 3-5% accuracy; used generically without that fitting, error widens to 8-12%.
Why still use an 1873 formula alongside modern interior ballistics software?+
Its simple algebraic form makes it fast to apply and easy to sanity-check by hand, useful as a quick cross-check or when detailed pressure-time data for a modern simulation is not available.
Related terms
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