Keyhole Wound
Definition
An asymmetric teardrop-shaped bullet entry hole produced when the bullet strikes the surface sideways or is unstabilised, indicating close-range fire (pre-stabilisation) or a bullet destabilised by an intermediate target.
- Location
- Skin, entry wound
- Shape
- Asymmetric, teardrop
- Cause
- Sideways or unstabilised bullet strike
- Indicates
- Very close range fire or destabilisation by an intermediate target
Common questions
Why would a bullet strike the skin sideways rather than nose-first?+
A bullet is most unstable immediately after leaving the muzzle, before spin stabilises its flight, so a very short firing distance can produce a keyhole wound; the same tumbling effect can also occur further out if the bullet first passed through glass, wood, or another intermediate barrier.
Should a keyhole wound on skin be confused with a keyhole defect on bone?+
They share a name and a similar underlying cause, an off-axis or unstable bullet strike, but they describe different tissues and different diagnostic details, entry-wound shape in skin versus internal beveling pattern in bone, so each is assessed with its own criteria.
Related terms
- Angle of Impact
- The angle between the bullet's trajectory and the surface it penetrates, measured from the surface plane. Calculated from entry-hole geometry: sin(angle) =...
- Bullet Trajectory Kit (BTK)
- A laser-based trajectory projection system by Sirchie that replaces the physical rod with a laser module, projecting a visible beam along the...
- Bullet Wipe (Metal Wipe)
- The grey-black ring of bullet-jacket material (grease, metal oxides, carbon) deposited around the margin of an entry hole as the bullet's periphery...
- Burke and Rowe 1992
- The primary peer-reviewed study of bullet ricochet behaviour on concrete, asphalt, and vehicle metal surfaces, published in the Journal of the Forensic...
- Faro Focus 3D
- A terrestrial laser scanner used for crime-scene documentation, capturing a full-resolution point-cloud model of the scene at millimetre accuracy. Trajectory rods or...
- Ortho-Tron Projection Rod
- A commercial trajectory rod system manufactured by Sirchie, widely used by the FBI Evidence Response Team and forensic laboratories internationally, providing standardised...
- Ricochet
- The deflection of a bullet off a surface at a low angle of incidence, producing a new trajectory that diverges from the...
- Single-Bullet Trajectory Analysis (JFK/HSCA)
- The 1979 House Select Committee on Assassinations photogrammetric reconstruction of the Kennedy assassination trajectories, the most extensively reviewed shooting reconstruction in forensic...
- 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...