Lands
Definition
The raised ridges of a rifled barrel. Lands engrave groove impressions into the surface of a passing bullet. They are the harder counterpart to the recessed grooves between them.
- Definition
- Raised ridges of a rifled barrel
- Effect on bullet
- Engrave groove impressions
- Counterpart
- Grooves (recessed sections between lands)
- Used in
- Rifling characteristic identification
Common questions
Why do land and groove impressions matter for firearm identification?+
Their width, number, and twist direction narrow the pool of possible firearm makes and models, giving an examiner a class-characteristic starting point before moving to individual toolmark comparison.
How can lands still leave individualising marks despite being a class characteristic?+
Manufacturing tool wear leaves microscopic striations on the land surfaces unique to that barrel, so while land count and width are class characteristics shared across many guns of the same model, the fine striae they engrave on a bullet can be individualising.
Related terms
- BKA
- Bundeskriminalamt, the German Federal Criminal Police Office, which operates the German GRC and ballistic identification database feeding the European EBIS network.
- CFSL
- Central Forensic Science Laboratory: a central government lab operating under DFSS. India has CFSLs at New Delhi, Hyderabad, Chandigarh, Kolkata, Pune, Guwahati,...
- General Rifling Characteristics (GRC)
- The class-level barrel properties (land count, groove count, land width, groove width, twist direction, twist rate) that allow a fired bullet to...
- Grooves
- The recessed channels cut into a rifled barrel between the lands. They create raised land impressions on a fired bullet's surface.
- Left-Hand Twist (LHT)
- Rifling that spirals counterclockwise toward the muzzle. The defining house convention of Colt Manufacturing Company and of the Lee-Enfield rifle family.
- NABIS
- National Ballistics Intelligence Service; the UK police intelligence service that maintains a national headstamp and firearm reference collection and coordinates ballistic intelligence...
- Polygonal Rifling
- A rifling form that uses a rounded hexagonal or octagonal bore profile instead of discrete lands and grooves. Characteristic of Glock barrels;...
- Rate of Twist
- The barrel length required for the rifling to complete one full helical revolution, expressed as a ratio (e.g. 1:9 means one complete...
- Right-Hand Twist (RHT)
- Rifling that spirals clockwise toward the muzzle when viewed from the breech. Used by the majority of the world's firearm manufacturers.