Calypso Ballistics

Calypso Ballistics turns a Calypso Instruments ultrasonic anemometer into a wind call you can trust. Pair the sensor over Bluetooth, set your line of fire, and the app reads the wind where you are standing — not from a forecast, not from a flag, and not from a guess.

THE DIAL The wind rose sits at the centre of the shot screen. It shows where the wind comes from relative to your line of fire, on the clock face shooters already use, with the shaded sector marking the angles where a shift moves your hold the most. Tap it to enlarge.

THE HOLD Below the dial, the number that matters: your wind hold, in MIL — or MOA and turret clicks in Pro mode. It is worked out from the crosswind component, your drift constant and your target distance, so the figure you read is the figure you dial.

THE BRACKET Wind is never one number. The bracket tracks the lull and the gust over a window you choose, so you can see the range you are shooting inside and time your shot to the condition you want rather than the one you happened to get.

ATMOSPHERE THAT GOES IN YOUR DOPE Density altitude and air density, worked out from temperature, pressure and humidity, with the full moist-air calculation shown if you want to check it. Pair the optional WeatherDot for measured temperature, humidity and pressure at the firing point; without one, the app falls back to the Open-Meteo weather model for your position and says so, so you always know whether you are reading a measurement or a model.

THREE MODES, NOT ONE Simple gives you the dial, the hold and the bracket and nothing else. Normal adds the full readout grid. Pro adds MOA and clicks, two more readouts and the complete atmosphere page. Every readout tile can be reassigned with a tap — put crosswind, gust hold, density altitude or o'clock wherever you want them.

LOGBOOK AND CHARTS Every session is recorded while the sensor is connected: wind speed and direction, gust, temperature, humidity and pressure. Review any outing on the charts, then export it as CSV to take the conditions away with your targets.

BUILT FOR THE RANGE Line of fire captured from the compass or set by hand. Keep-screen-awake for the wait between shots. Text size that stays readable at arm's length. Units for wind speed and distance to suit you. Auto-reconnect to the last sensor when you open the app. In English and Spanish.

HARDWARE REQUIRED This app reads from Calypso Instruments Bluetooth anemometers. Without one paired it has nothing to measure — the atmosphere page and the calculations still work, but the wind readings come from a sensor you supply. To try the app first, turn on Demo mode in Settings › Sensor for simulated wind.

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