Density Altitude Simulator[beta]

Weights and Measures Notes

Density Altitude

DA is estimated with a simplified rule-of-thumb formula referenced to the International Standard Atmosphere (15 °C at sea level, −2 °C per 1,000 ft of lapse): DA = Elevation + 120 × (OAT°C − ISA°C). Field elevation and temperature are the only inputs — pressure and humidity are not factored.

Point-of-Impact Shift

Vertical shift is driven by a generalized range-dependent mil-per-1,000-ft-ΔDA coefficient, power-law fit per caliber. This replaces a flat mil-per-1,000-ft rule, since sensitivity to DA actually grows with range.

Calibers

Each caliber (5.56, .308 Win, 6.5 Creedmoor) has its own fitted coefficient, reflecting that flatter-shooting, higher-BC bullets are less sensitive to a given DA change than lower-BC bullets.

Cone of Fire

The optional dispersion circle is a group diameter in inches, set at a 100-yard baseline. Because dispersion is angular (MOA), it scales linearly with true physical distance to the current range.

Unit Conversions

• 1 mil ≈ 3.6" per 100 yards
• 1 MOA ≈ 1.047" per 100 yards
• Range and shift figures convert directly between yards and meters

Disclaimer

This tool is a simplified illustrative model, not a ballistic solver. It is only to be used to visualize approximations of the effect of DA on point of impact.