The Aimpoint CompM4 is a non-magnified red dot style gun sight adopted by the U.S. Armed Forces, designated the M68 CCO (Close Combat Optic). It is produced by the Swedish company Aimpoint and is the successor to the earlier M68CCO, the Aimpoint CompM2.
The Aimpoint CompM4 is a "tubed" style reflector (reflex) sight that uses a red light-emitting diode (LED) at the focus of a mirror type optical collimator to produce an aligned red aiming spot (what is commonly called a red dot sight ). There are a total of 16 brightness settings for the LED, the lower 7 intended for use with night vision devices and the upper 9 for daylight. The CompM4 is powered by a standard AA battery, and the manufacturer claims that the sight will run continuously for 8 years on a single battery, in its 10th brightness setting.
Reflector sights have unlimited eye relief, meaning that the user may place his eye at any distance from the sight and the reticle will remain visible. This allows flexibility in mounting and shooting position. The CompM4 uses Aimpoint's "parallax-free" optical correction system, meaning there is minimal induced optical error that would shift the point of aim relative to the sight's optical axis as the user's eye moves off-center in relation to the sight. The sight itself is parallax-free at around 50 yards, meaning that the red dot will not change position relative to the target based on eye position at that range. As in other reflex sights, the point of aim will change position based on eye position at other ranges with the maximum error being equal to the diameter of the sight's optical window at short range. [1] There are currently two variants available; the standard CompM4 and the CompM4S, the latter being the same in terms of features and functionality, but having the battery compartment & power control knob mounted near the bottom of the sight instead of near the top.
In 2009, the US Army selected the CompM4s to fulfill the M68 CCO program requirements and ordered 565,783 of the sights. [2] This was followed by another order in 2017 for an additional 30,000 sights. [3]
Afghanistan: Used by Afghan Commandos on M4 carbine 
Armenia: Used by Armenian Special Units.
Belgium : Used by most Belgian Defence soldiers equipped with FN SCAR. [4] 
Chile 
Czechia : Used by Army of the Czech Republic soldiers equipped with CZ 805 BREN. [5] 
Greece: Used by Hellenic Army SF.
Netherlands: Used by the Armed forces of the Netherlands on the C7NLD, C8NLD, LOAWNLD, FN Minimi and the HK416. [6] 
India: Used by the Indian Army's Para (Special Forces) and Force One of the Mumbai Police on M4 carbine. [7] 
Iraq: Used by ISOF. [8] 
Lebanon 
Norway [9] 
Portugal: Used by Portuguese Army, Portuguese Marine Corps and Guarda Nacional Republicana. [10] 
United States 
The M4 carbine is a 5.56×45mm NATO, gas-operated, magazine-fed carbine developed in the United States during the 1980s. It is a shortened version of the M16A2 assault rifle.
The Colt Canada C7 and C8 are a Canadian family of service rifles, manufactured by Colt Canada, having similar design and function to the Colt M16A3.
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The CompM2 is a battery-powered, non-magnifying red dot type of reflex sight for firearms manufactured by Aimpoint AB. It was first introduced in the U.S. Armed Forces in 2000, designated as the M68 Close Combat Optic. It is also known as the M68 Aimpoint and is designed to meet United States military standards. The sight is designed for use with the M16/M4 family of rifles, but can be mounted on any weapon fitted with an upper Picatinny rail. It is also NVG-compatible—the aiming dot is still visible through night vision scopes and goggles. The Army's M68 designation was also applied to a later version of the sight, the Aimpoint CompM4.
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A designated marksman rifle (DMR) is a modern scoped high-precision rifle used by infantry in the designated marksman (DM) role. It generally fills the engagement range gap between a service rifle and a dedicated sniper rifle, at around 300–600 metres (330–660 yd).
Aimpoint AB is a Swedish optics company based in Malmö, Sweden that manufactures red dot sights.
The Heckler & Koch HK416 is an assault rifle chambered for the 5.56×45mm NATO cartridge. It is designed and manufactured by the German company Heckler & Koch.
The Special Operations Peculiar MODification (SOPMOD) kit is an accessory system for the M4A1 carbine, CQBR, FN SCAR Mk 16/17, HK416 and other weapons used by United States Special Operations Command (USSOCOM) special forces units, though it is not specific to SOCOM. The kit allows US Special Operations Forces personnel to configure their weapons to individual preferences and customize for different mission requirements.
The M6 is a series of carbines designed and manufactured by LWRC International. It is based on the M4 carbine, with which it shares 80% of its parts. The 'M' model name is not a US military designation. Like the HK416, it features a proprietary short-stroke self-regulating gas piston system and bolt carrier/carrier key design, which prevents trapped gases from contacting the bolt carrier or receiver of the weapon. The manufacturer claims that this reduces the heating and carbon fouling of the internals, simplifies field maintenance, and improves reliability.
The C79 Optical sight is a small arms telescopic sight. Elcan names it as the SpecterOS3.4x, but in Canadian service, it is typically referred to as the C79 or the C79A2. A variant, the M145 Machine Gun Optic is in use by the US military. It is 3.4×28, meaning 3.4x magnification, and a 28mm diameter objective lens. A tritium illuminated reticle provides for normal and low-light conditions sighting. It can be mounted to a variety of rifles and light machine guns using the M1913 Picatinny rail mounting system or the similar "Diemaco" rail system found on small arms produced by Diemaco/Colt Canada. It is manufactured by Elcan and can be found on military service weapons around the world. Similar rifle sights are the Sight Unit Small Arms, Trilux (SUSAT) and the Advanced Combat Optical Gunsight (ACOG).
A red dot sight is a common classification for a non-magnifying reflector sight that provides an illuminated red dot to the user as a point of aim. A standard design uses a red light-emitting diode (LED) at the focus of collimating optics, which generates a dot-style illuminated reticle that stays in alignment with the firearm the sight is attached to, regardless of eye position.
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The Ak 4 is a license-built Swedish version of the West German Heckler & Koch G3 battle rifle. It was adopted as the service rifle of the Swedish Armed Forces in 1965, replacing the bolt-action m/96 Mauser.
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