Vital Zone
Definition
The defined target area used to compute point-blank range. For human thorax: typically 20 cm diameter (10 cm radius) centred on the heart/lung complex.
- Body region
- Human thorax
- Typical diameter
- About 20 cm
- Typical radius
- About 10 cm
- Centred on
- Heart and lung complex
- Used in
- Point-blank range calculations
Common questions
Why does point-blank range depend on the size of a target zone rather than a single point?+
Point-blank range is defined as the maximum distance at which a projectile fired on a level trajectory still strikes within the vital zone, given bullet drop. A single aiming point would ignore that a hit anywhere across the chest is still lethal, so the calculation uses the zone's radius as the allowable drop.
Does the vital zone dimension change for other targets, such as game animals?+
Yes. Ballistics texts define separate vital zone dimensions for different targets, for example a smaller radius for deer-sized game than for a human thorax, because the lethal target area differs by species and anatomy.
Related terms
- Ballistic Solver
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- Battle-Sight Zero (BZO)
- The zero range selected by a military or paramilitary organisation as the standard setting for field use. US Army M4: 300 m....
- Bore Axis
- The centreline of the barrel through which the bullet travels. The starting reference line for measuring gravity drop and the elevation difference...
- Gravity Drop
- The vertical distance a bullet falls below the bore axis at a given horizontal range, accumulating continuously from the instant of muzzle...
- Near-Zero Crossing
- The shorter of the two distances at which the bullet's trajectory intersects the line of sight. For a rifle zeroed at 300...
- Point-Blank Range (PBR)
- The maximum distance at which the bullet stays within the vital-zone radius above or below the line of aim without the shooter...
- Trajectory Rod
- A rigid fibreglass or aluminium rod inserted through a bullet wound channel and aligned with the channel geometry to define the bullet's...
- Zero Range
- The horizontal distance at which the bullet's trajectory crosses the line of sight. At this range, the point of aim and point...