The Colt Advanced Piston Carbine or Colt APC is a lightweight modular 5.56mm caliber piston-operated, magazine fed carbine with a one-piece

upper receiver In firearms terminology, the firearm frame or receiver is the part of a firearm which integrates other components by providing housing for internal action components such as the hammer, bolt or breechblock, firing pin and extractor, and has th ...

which is capable of firing in automatic and semi-automatic modes. The design incorporates an articulating link piston that reduces the stresses in the piston stroke by allowing for deflection and

thermal expansion Thermal expansion is the tendency of matter to change its shape, area, volume, and density in response to a change in temperature, usually not including phase transitions. Temperature is a monotonic function of the average molecular kinetic ...

Design

The weapon has a suppression-ready fluted barrel, which is lighter and cools better than previous M4 barrels. It is claimed to have "markedly better" accuracy. To improve reliability, Colt used an articulating link piston (ALP) which "reduces the inherent stress in the piston stroke by allowing for deflection and thermal expansion". In traditional gas piston operating systems, the force of the piston striking the bolt carrier can push the bolt carrier downwards and into the wall of the buffer tube, leading to accelerated wear and even chipped metal. This is known as carrier tilt. The ALP (articulating link piston) allows the operating rod to wiggle to correct for the downward pressure on the bolt and transfers the force straight backwards in line with the bore and buffer assembly, eliminating the carrier tilt. This relieves stress on parts and helps to increase accuracy.

Users

Malaysian Special Operations Force The National Special Operations Force (NSOF) ( ms, Pasukan Operasi Khusus Nasional) was Malaysia's main security force which serves as the first responder to any terror threats on the country's sovereignty. The force covers elements from the Mala ...

units, the UTK and the VAT69 *:

Singapore Police Force The Singapore Police Force (SPF) is the national and principal law enforcement agency responsible for the prevention of crime and law enforcement in the Republic of Singapore. It is the country's lead agency against organised crime; human, wea ...

, Used by

Police Coast Guard Special Task Squadron The police are a constituted body of persons empowered by a state, with the aim to enforce the law, to ensure the safety, health and possessions of citizens, and to prevent crime and civil disorder. Their lawful powers include arrest and th ...

and

Emergency Response Team An incident response team (IRT) or emergency response team (ERT) is a group of people who prepare for and respond to an emergency, such as a natural disaster or an interruption of business operations. Incident response teams are common in public s ...

References

External links

Colt's Manufacturing Company Official
5.56 mm firearms Assault rifles Carbines Colt rifles Rifles of the United States ArmaLite AR-10 derivatives {{Rifle-stub