Range Card

Stadiametric Rangefinding

Game Species · South Africa

Adult shoulder height (at the withers) is the standard reference point for this kind of estimate, sourced from field guides and hunting references. Those published figures are the male animal. Female, calf and young-adult figures aren't independently published for most species — females are scaled by a per-species dimorphism band (equal, modest, clear or strong), and calf/young adult by 55% and 90%, based on typical ungulate growth patterns. Anything marked ~ is a derived estimate, not a measurement — treat it as a starting point and check against your own references.

Scope Adjustment

Enter the table printed on your ammo box below. Velocity drives the calculated drop; energy is shown at your target distance for reference. If you also fill in the manufacturer's trajectory column, those published figures are used directly instead of the estimate — but only while your zero matches the zero that table was measured at.

Bullet velocity, energy & trajectory table

Range (m)

Velocity (m/s)

Energy (J)

Traj. (mm)

Trajectory is the bullet's path relative to your line of sight: positive is above, negative below, and 0 marks the zero range. Leave the muzzle row blank.

Scope & zero settings

Adjustment unit

Click value

mil

Total travel (each way)

mil

Zero distance

Sight height over bore

Target distance

Auto-filled by the "→ Use this range in Ballistics" button on the Scope (MIL) or Binoculars (FOV) tabs.

Time of flight (from velocity table)

t(Zero) and t(Target) — integrated from your velocity table, segment by segment

→ t(zero) = 0.000 s · t(target) = 0.000 s

Gravity drop at each distance

h = ½ × g × t² (g = 9.807 m/s²)

→ h(zero) = 0.000 m · h(target) = 0.000 m

Drop relative to line of sight at target

Drop = (D÷Z)×(h_Z+S) − S − h_D

→ Drop = 0.000 m

Required angular correction

Angle = |Drop| ÷ D → converted to MIL / MOA

→ 0.00 MIL (0.0 MOA)

Clicks to dial

Clicks = Angle ÷ Click value

→ 0 clicks

Dial Direction & Clicks

0 clicks UP

≈ 0.00 MIL · 0.0 MOA

At target distance (reference)

Velocity: — · Energy: —

Reusable formula

Drop = (D/Z)(h_Z+S) − S − h_D | Clicks = (|Drop|/D) ÷ click value

Simplified flat-fire model: assumes level ground (no incline/decline), no wind or spin drift, and linear interpolation between your table rows. Velocity/time is derived directly from your box's own printed data rather than a generic ballistic coefficient, which is a reasonable approximation for typical hunting ranges — for competition-grade precision at long range, a full drag-curve solver will be more accurate.

Quick reference — clicks by distance

Recalculates live from the zero, sight height, and bullet table above. The row matching your current zero is highlighted (0 clicks, by definition).

Range

MIL

MOA

Clicks

Software

Version —

Updates are only checked when you press the button.

Display

Compact mode

Hides the step-by-step working and all explanatory text, leaving only the fields you fill in and the results. Warnings still show.

Sensor filtering

Combats jumpy gyro/compass/GPS readings with a moving-average window and a sampling-rate throttle, each independently tunable per sensor. Turning on "Drop outlier readings" rejects a reading that jumps far outside the recent trend instead of blending it into the average. The same three controls are also one tap away via the ⚙ next to each stability badge on the Video, Compass and Level tabs.

Enable sensor filtering

Turn off to see completely raw, unfiltered readings everywhere below — no smoothing, no outlier rejection. Handy for checking whether a sensor itself is unstable, independent of these settings.

Gyro (tilt)

Window size (samples)

Sampling rate (Hz)

Drop outlier readings

Rejects a gyro reading that jumps far outside the recent trend.

Compass (heading)

Window size (samples)

Sampling rate (Hz)

Drop outlier readings

Rejects a heading that jumps far outside the recent trend.

GPS location

Window size (fixes)

Sampling rate (Hz)

Drop outlier readings

Rejects a GPS fix that jumps far outside the recent trend.

Sensor log

Keeps a rolling 5-minute buffer of the raw, unsmoothed gyro/compass readings (from the Compass, Level and Video tabs) and GPS fixes (from the Video tab's mini-map), entirely on this device — nothing is sent anywhere. Handy for analysing a jumpy reading afterwards.

No samples logged yet — enable Compass, Level or Video to start recording.

Scope reticle

How many mils your reticle covers from the centre crosshair out to the edge of the view. This caps how far the Scope tab can zoom out.

Reticle span ± (mil)

±10 mil · 20 mil total

Scope presets

Turret and zero details for a specific rifle/scope. Applying one fills in the Ballistics tab.

Preset name

Turret unit

Click value

Total travel

Zero (m)

Sight height (cm)

Reticle span ± (mil)

Binocular presets

Magnification and apparent field of view for a pair of binos. Applying one fills in the Binos · FOV tab.

Preset name

Magnification (×)

Apparent FOV (°)

Bullet / load presets

The default velocity and energy table for a load. Applying one fills the Ballistics table. Values normally come off the ammunition manufacturer's data sheet.

Preset name

Range (m)

Velocity (m/s)

Energy (J)

Traj. (mm)

Storage

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