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Support
How to measure a group, what each message means, and how to reach us.
Measuring a group
- Open a session (it holds the distance, bullet caliber and your scope's click value) and tap Add a Group.
- Take a photo or choose one. Keep the whole reference rectangle in the frame: the sheet, or a block of grid squares.
- Tap the rectangle's four corners and check its width and height. The orange arrow marks the top of the target; tap the rotate button if the photo is sideways.
- The blue cross starts at the centre of the rectangle. Tap or drag it to your point of aim.
- Tap the centre of each hole. Pinch to zoom, drag a mark with the magnifier, or select it and use the arrow buttons. Then tap Done and Save Group.
Tips for accurate results
- Use the largest rectangle you can. A single 1 inch square works, but small tapping errors grow with the distance from it.
- Keep the paper flat and fill the frame with the target. Angle is fine; a curled sheet or a fish-eye lens is not.
- Zoom in before you tap tight groups, and tap the centre of each hole, not its edge.
- Most scopes use true MOA. Choose shooter's MOA in Settings only if your turret says 1/4 inch at 100 yards.
Check your setup with a printed target
Print the calibration target at 100 % (actual size) on US Letter paper. Its five dots form a group with an extreme spread of exactly 1.000 inch, centre to centre. Photograph it at an angle, measure it with the whole sheet as the reference (8.5 × 11 in), and the extreme spread should read close to 1.00 in.
What the messages mean
| Message | What to do |
|---|---|
| These corners don't form a rectangle outline | One corner is inside the others. Drag it to the real corner. |
| The rectangle in the photo doesn't look like this width × height | The size you entered doesn't match the shape. Check the numbers, or swap width and height. |
| Small reference | Your rectangle is small in the photo. Use the whole sheet or a bigger block of squares if you can. |
| needs 2 shots | Standard deviation needs at least two holes. |
Composite groups and export
A session with two or more groups shows a composite: every hole from every group, each group aligned on its own point of aim. Use the … menu on a session to export two CSV files (groups and shots), or the menu on a group to share an annotated image. Settings has a sample session with five measured groups to try it.
Contact: kl@fireinbelly.com. Include your device model, iOS version and, if you can, the photo you measured.