Line-of-sight geometry
Zero-Distance Visualizer
See why a path can cross your line of sight twice—and how velocity, optic height, and zero distance move both intersections.
This is a geometry visualizer, not a firing solution. It models sight height, bore angle, initial muzzle velocity, and gravity with no aerodynamic deceleration. It intentionally excludes ballistic coefficient, atmosphere, wind, spin, and real velocity loss.
Modeled path
Height relative to line of sight
Modeled pathLine of sight
Reference points
Modeled offsets
Positive values are above the line of sight; negative values are below it.
| Distance | Path | Relationship |
|---|
What the curve means
The sight starts above the bore.
At the muzzle, the modeled path begins below the line of sight by exactly the entered sight height. The bore is angled slightly upward relative to the sight line, so the path may cross once nearby, rise above it, then cross again at the downrange zero.
When precision matters
Switch to a full ballistic solver.
Real trajectory depends on drag model, ballistic coefficient, changing velocity, temperature, pressure, altitude, and the actual firearm/ammunition combination. Verify any real zero at the range; never treat this educational curve as a field correction.
Primary references
Definitions and full solvers
- OpenStax: projectile motion — the no-drag horizontal/vertical motion equations used by this model.
- Federal Ammunition: trajectory basics — the two line-of-sight crossings described by the visualizer.
- Federal Ballistics Calculator — a full solver that accepts ballistic coefficient, atmosphere, sight height, and zero range.
- Vortex ballistic-input definitions — measuring sight height and verifying muzzle velocity.
- Optics Intel: How to Zero an LPVO — the live-fire process and confirmation groups.