GRC Database
Definition
General Rifling Characteristics database maintained by the FBI Laboratory's Firearms and Toolmarks Unit; includes an ammunition component section that references headstamp codes against production histories and user-state distributions.
- Full name
- General Rifling Characteristics database
- Maintained by
- FBI Laboratory, Firearms and Toolmarks Unit
- Ammunition component
- Headstamp codes cross-referenced to production history
- Use
- Narrows candidate firearm makes and models
Common questions
How does an examiner use the GRC database in practice?+
The examiner measures the land and groove count, direction of twist, and land and groove widths from a fired bullet, then queries the database for firearm makes and models known to produce that rifling signature, which narrows the field of possible source weapons before any specific gun is recovered.
Does a GRC database match identify the exact firearm that fired a bullet?+
No. It only narrows the class of firearms consistent with the class characteristics observed, individualisation to one specific gun still requires microscopic comparison of the bullet's individual striations against a test-fired bullet from the recovered weapon.
Related terms
- CIP
- Commission Internationale Permanente pour l'Epreuve des Armes a Feu Portatives; the European proof body that standardises chamber and cartridge specifications for European...
- Imperial Calibre Notation
- Calibre designation using decimal fractions of an inch, often with a name suffix indicating the designer or intended firearm (e.g. .45 ACP,...
- IOF
- Indian Ordnance Factory headstamp code (produced at Khadki / Kirkee, Pune); the primary Indian government producer of 9x19mm, .38 Special, and 7.62x51mm...
- LC
- Lake City Army Ammunition Plant headstamp code; the primary US military ammunition producer for small-arms calibres including 5.56x45mm, 7.62x51mm, and .50 BMG.
- Metric Calibre Notation
- Calibre designation using bullet diameter in millimetres multiplied by case length in millimetres (e.g. 9x19mm, 7.62x39mm, 5.56x45mm); standard in NATO and European...
- NABIS
- National Ballistics Intelligence Service; the UK police intelligence service that maintains a national headstamp and firearm reference collection and coordinates ballistic intelligence...
- NATO Cross
- A circle with cross symbol stamped on military cartridge headstamps confirming the round meets the relevant NATO STANAG specification; found on production...
- Primer Sealant
- Coloured lacquer applied at the primer-to-case-head junction on military cartridges to prevent moisture ingress; colour varies by manufacturer and is not a...
- RG
- Radway Green headstamp code (UK); BAE Systems' Royal Ordnance Factories facility and primary UK military small-arms ammunition producer.
- S+B
- Sellier and Bellot headstamp code (Czech Republic, now part of CBC Group); a major European commercial and military-contract producer exported globally including...
- SAAMI
- Sporting Arms and Ammunition Manufacturers' Institute; the US voluntary standards body that publishes chamber and cartridge drawings and maximum average pressure (MAP)...