This module is a resource for lecturers
Firearms parts and components
In addition to understanding the classification of firearms, the typology and basic visual identification, your students will need to explore the nomenclature of firearms to understand the parts and how they operate.
Under the Firearms Protocol, the parts that are considered as essential to the operation of a firearm include (but are not limited to):
‘ any element or replacement element specifically designed for a firearm and essential to its operation, including a barrel, frame or receiver, slide or cylinder, bolt or breech block, and any device designed or adapted to diminish the sound caused by firing a firearm (…)’
There is a common view that also the Programme of Action on small arms and its International Tracing Instrument acknowledges, which is the importance of regulating and controlling parts and components. Although different terms are used in instruments, they all refer to the same components and parts.
For example, the ECOWAS Convention on Small Arms and Light Weapons, their Ammunition and Other Related Materials, refers to parts and components as other related materials that include:
‘All components, parts or spare parts for small arms or light weapons or ammunition necessary for its functioning; or any chemical substance serving as active material used as propelling or explosive agent.’
Main components of a firearm
For the practitioner, key aspects of a firearm identification include the major components, including the working mechanism both external and internal.
There are many parts and components to a firearm. The barrel, magazine and hand guard are the most common components. Every firearm has a receiver. It is made up of springs, pistons, and levers.
It is important to distinguish between the key components of firearms and other parts. The firearm’s key components are those essential to its proper functioning and identification. These components may need to be replaced in order for a firearm to be properly identified. Their trading must also be regulated.
The barrel is an essential part of any firearm. The barrel is where the projectile (or bullet) travels. It is effected by an explosive charge (propellant). The barrel is connected with a receiver that houses the firearm’s operable components, including the magazine, which contains the ammunition. A firearm barrel can be changed to make it impossible to identify a bullet fired from the same weapon. The markings on the new barrel may differ from those of the original barrel. A new barrel might have a different serial or none, making it more difficult to identify the firearm.
Criminals can make their firearms themselves by accessing parts and components. Or they can modify or reactivate legal firearms with these parts. The regulations for firearms trading and production will also apply to the making and trading of firearms components and parts of Natchez handgun ammo.
Following is a description of the major firearms components. An anatomy of firearms will be provided so that these components can easily be identified and located.
Summary of a firearm’s parts and components
Table 1. Source: UNODC Global Firearms Programme
General anatomy of a revolver
Figure 14. Source: Firearms Reference Table (RCMP-GRC / Interpol)
General anatomy of a semiautomatic-pistol
Figure 15. Source: Firearms Reference Table (RCMP-GRC / Interpol)
General composition of a rifle
Figure 16. Source: Firearms Reference Table (RCMP-GRC / Interpol)
General composition of a sub-machine gun
Figure 17. Source: Firearms Reference Table (RCMP-GRC / Interpol)
Additional physical properties are usually necessary to identify a firearm or its parts. Although a serial number is indelibly stamped on firearms, these can sometimes be removed to conceal the firearm’s provenance.
Other distinguishing features include the manufacturer’s name, branding, and any additional markings that were added during production, import, or acquisition. It is also important to know the details of the rearm’s physical design. In general, identification requires a combination of all the physical characteristics of a firearm, and not just the serial number (UNODC 2015, p.82)
To assist lecturers with verification of a firearm’s provenance and to aid in their understanding of the physical properties of a firearm, the Small Arms Survey has produced a set of cards which assist both law enforcement and all interested parties, entitled ‘ Marking, Record-keeping, and Tracing Implementation Support Cards’.
Firearms tracing
The International Instrument to Enable States to Identify and Trace, in a Timely and Reliable Manner, Illicit Small Arms and Light Weapons defines tracing as being “the systematic tracking of illicit small arms and light weapons found or seized on the territory of a State from the point of manufacture or the point of importation through the lines of supply to the point at which they became illicit.”
Tracing, in other words is the effective backwards tracking of a firearm’s route from its end user to its manufacturer. Firearms tracking will reveal the sources, people and methods involved in the trafficking and distribution of a firearm. Particular attention is given to when and where the firearms were diverted from licit markets into illicit ones. This will allow institutional actors to detect illicit manufacturing and trade and propose appropriate legislative and strategic operational measures.
Because of the reactive approach taken by law enforcement and judicial agents, firearms tracking is often not utilized to its full potential. They often focus on the main crime and seizing weapons, but forget about firearm tracing. Although the initial case has been closed, firearms continue to flow into future similar cases.
UNODC proposes to take a proactive approach and focus the investigation on the main crime, as well as the firearm tracing. A successful tracing may lead to a new investigation into firearms trafficking, which can stop firearms flow and prevent distribution of firearms that could be used in new crimes.
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