TheM4 carbine(officiallyCarbine, Caliber 5.56 mm, M4) is a5.56×45mm NATOassault rifledeveloped in the United States during the 1980s. It is a shortened version of theM16A2assault rifle.

Carbine, Caliber 5.56 mm, M4
Colt M4 carbine withRAS,M68 CCO
TypeAssault rifle
Carbine
Place of originUnited States
Service history
In service1994–present
Used bySeeUsers
WarsSeeConflicts
Production history
Designed1982–1993
Manufacturer
Unit cost$700 (avg. cost) in 2012[1]
$647 per unit in 2015
Produced1987–present[2]
No.built500,000[3]
VariantsSeeVariants
Specifications
Mass6.43 lb (2.92 kg) empty[4]
7.75 lb (3.52 kg) with 30 rounds loaded magazine andsling
Length33 in (838 mm) (stockextended)
29.75 in (756 mm) (stock retracted)
Barrellength14.5 in (368 mm)

Cartridge5.56×45mm NATO
ActionGas-operated,closedrotating bolt,Stoner expanding gas
Rate of fire700–970 rounds/min cyclic[5]
Muzzle velocity2,970 ft/s (910 m/s) (M855A1round)[6]
2,887 ft/s (880 m/s) (M855 round)
2,986 ft/s (910 m/s) (M193 round)
Effective firing range500 m (550 yd) (individual/point targets)[5]
600 m (660 yd) (area targets)[5]
Maximum firing range3,600 m (3,900 yd)[5]
Feed system30-round detachableSTANAG magazine[a]
SightsIron sightsor various optics

The M4 is extensively used by theUS military,with decisions to largely replace the M16 rifle inUS Army(starting 2010) andUS Marine Corps(starting 2016) combat units as the primaryinfantryweapon[7][8]andservice rifle.The M4 has been adopted by over 60 countries worldwide,[9]and has been described as "one of the defining firearms of the 21st century".[10]

Since its adoption in 1994,[9]the M4 has undergone over 90 modifications to improve the weapon'sadaptability,ergonomicsandmodularity,including: the M4A1, which strengthened the barrel and replaced theburst-fireoption with afully automaticoption; theSOPMOD,an accessory kit containing optical attachments; and the underbarrel weapons such asM203andM320grenade launchersto theMasterkeyandM26-MASSshotguns.

In April 2022, the U.S. Army selected theXM7 rifle,a variant ofSIG MCX Spear,as the winner of theNext Generation Squad Weapon Programto replace the M16/M4.[11]

History

Development of the M4

Following the military adoption of theArmalite AR-15as theM16 rifle,carbine variants were also adopted forCQCoperations,[12]the first of which was theCAR-15family of weapons, which was used in theVietnam War.[13]However, these rifles had design issues, as thebarrellength was halved to 10 inches (25 cm), which upset theballistics,reducing its range and accuracy and leading to considerablemuzzle flashand blast,[14]meaning that a largeflash suppressorhad to be fitted.[15]

In 1982, the U.S. Government requestedColtto make a carbine version of the M16A2. At the time, the Colt M16A2 was the Colt 645, also known as the M16A1E1. Later that year, the U.S. Army Armament Munitions Chemical Command helped Colt develop a new variant of the XM177E2, and the U.S. Army redesignated the XM177E2 to the XM4 Carbine, giving the name as the successor to theM3 carbine.The carbine used the same upper and lowerreceiveras the M16A1,[16]and fires the M855 cartridge along with the older M193 cartridges. In 1983, the9th Infantry Divisionrequested a Quick Reaction Program (QRP) for a5.56mmcarbine to replace the M1 carbine andM3 submachine gunin service.[17][14]The XM4 was tested by the Army's Armament Research and Development Center (ARDC) in June 1983. Later, the gun was updated with improved furniture, and a barrel with rifling of 1 turn in 7 inches (180 mm). The ARDC recommended additional commonality with the M16A2 rifle, as well as lengthening the barrel to 14.5 inches (370 mm).[16]In January 1984, the U.S. Army revised the QRP, and a month later, it formally approved development of the new carbine.[16]

In June 1985, thePicatinny Arsenalwas given a contract to produce 40 prototypes of the XM4.[16]Initially a joint program between the Army and Marines, in 1986 the Army withdrew their funding. The XM4 was finished in 1987, and the Marines adopted 892 for thatfiscal year,with the designation "carbine, 5.56mm, M4".[16]Owing to experience from the 1991Gulf War,the Army gave Colt its first production contracts for M4 carbines in May and July 1993, and M4A1 carbines forUnited States Special Operations Command(SOCOM) operators in February 1994.[18]

Interest in the M4 carbine was accelerated after theBattle of Mogadishu (1993),in whichRangerscomplained that their M16 rifles were "unwieldy", whereas members ofDelta Forcein the same battle, equipped with the CAR-15, had no such complaints.[19]The M4 carbine first saw action in the hands of U.S. troops deployed toKosovoin 1999 in support of theNATO-ledKosovo Force.[20]It would subsequently be used heavily by U.S. forces during thewar on terror,including inOperation Enduring Freedomand theIraq War.[20]In the Army, the M4 had largely replaced M16A2s as the primary weapon of forward deployed personnel by 2005.[21]The M4 carbine also replaced most submachine guns and selected handguns in U.S. military service,[21]as it fires more effective rifle ammunition that offers superiorstopping powerand is better able to penetrate modernbody armor.[20]

A10th Special Forces Groupsoldier with an M4 carbine during an exercise in July 1995
A U.S. Army82nd Airbornesoldier holds an M4 carbine inVitina,Kosovoin January 2000 during the NATO-ledKFORmission, the first operational use of the M4 by U.S. troops

In 2007, the USMC ordered itsofficers(up to therankoflieutenant colonel) andstaffnon-commissioned officersto carry the M4 carbine instead of theM9handgun.[22]This is in keeping with the Marine Corps doctrine, "Every Marine arifleman."[23]The Marine Corps, however, chose the full-sized M16A4 over the M4 as its standard infantry rifle.United States Navycorpsmen E5 and below are also issued M4s instead of the M9.[24]While ordinary riflemen in the Marine Corps were armed with M16A4s, M4s were fielded by troops in positions where a full-length rifle would be too bulky, including vehicle operators,fireteamand squad leaders. As of 2013, the U.S. Marine Corps had 80,000 M4 carbines in their inventory.[25][26]

By July 2015, major Marine Corps commands were endorsing switching to the M4 over the M16A4 as the standard infantry rifle, just as the Army had done. This is because of the carbine's lighter weight, compact length, and ability to address modern combat situations that happen mostly within close quarters; if asquadneeds to engage at longer ranges, theM27 Infantry Automatic Riflecan be used as adesignated marksman rifle.Approval of the change would move the M16 to support personnel, while armories already had the 17,000 M4s in the inventory needed to outfit all infantrymen who needed one.[27]In October 2015,CommandantRobert Nellerformally approved of making the M4 carbine the primary weapon for all infantry battalions, security forces, and supporting schools in the USMC. The switch was to be completed by September 2016.[28]In December 2017, the Marine Corps revealed a decision to equip every Marine in an infantry squad with the M27, while the M4 would be retained for leadership billets at the platoon level and above.[29]MARSOCalso retains the M4, as its shorter barrel is more suited to how they operate in confined spaces.[30]

Improved M4

In 2009, the U.S. Army took complete ownership of the M4 design.[31]This allowed companies other than Colt to compete with their own M4 designs. The Army planned on fielding the last of its M4 requirement in 2010.[31]In October 2009, Army weapons officials proposed a series of changes to the M4 to Congress. Requested changes included an electronic round counter that records the number of shots fired, a heavier "SOCOM barrel", and possibly replacing the Stoner expanding gas system with agas pistonsystem.[32][33]The heavier "SOCOM barrel" was first issued to special forces operators in the early 2000s to enable greater sustained automatic fire in certain immediate-action drills, although SOCOM itself would eventually return to the standard "government profile" barrel in its subsequent M4 improvement programs.[34]

The benefits of these changes, however, have come under scrutiny from both the military and civilian firearms community.[35]According to a PDF detailing the M4 Carbine improvement plans released by PEO Soldier, the direct impingement system would be replaced only after reviews were done comparing the direct impingement system to commercial gas piston operating system to find out and use the best available operating system in the U.S. Army's improved M4A1.[36]

In September 2010, the Army announced it would buy 12,000 M4A1s from Colt Firearms by the end of 2010, and would order 25,000 more M4A1s by early 2011. Additionally, the service branch planned to buy 12,000 M4A1 conversion kits in early 2011 and bought 65,000 more later that year. Eventually, the Army would upgrade all of its M4s to M4A1s, although the Marine Corps would largely abstain from the effort.[37]Conversion of M4s to the M4A1 in the Army began in 2011, as part of the Product Improvement Program, which included the conversion of 300,000 M4 carbines to the M4A1.[38]The101st Airborne Divisionbegan fielding newly built M4A1s in 2012, and theU.S. 1st Infantry Divisionbecame the first unit to convert their M4s to M4A1-standard in May 2014. Upgrades included the heavier SOCOM barrel to better dissipate heat from sustained automatic firing, the full-auto trigger group with a more consistent trigger pull than the burst group's to enable better semi-automatic accuracy, and the ambidextrous selector lever for easier use with left-handed shooters. The M4-M4A1 conversion increases weapon weight from 7.46 lb (3.38 kg) to 7.74 lb (3.51 kg), counting a back-up iron sight, forward pistol grip, empty magazine, and sling. Each carbine upgrade costs $240 per rifle, for a total cost of $120 million for half a million conversions. Three hundred conversions can be done per day to equip a brigade combat team per week, with all M4A1 conversions to be completed by 2019.[39][40]

In addition to upgrade kits, in April 2012, the U.S. Army announced it would begin purchasing over 120,000 M4A1 carbines to start reequipping front line units from the original M4 to the new M4A1 version. The first 24,000 were to be made byRemington Arms Company.Remington was to produce the M4A1s from mid-2013 to mid-2014.[41]After completion of that contract, it was to be between Colt and Remington to produce over 100,000 more M4A1s for the U.S. Army. Because of efforts from Colt to sue the Army to force them not to use Remington to produce M4s, the Army reworked the original solicitation for new M4A1s to avoid legal issues from Colt.[42]On 16 November 2012, Colt's protest of Remington receiving the M4A1 production contract was dismissed.[43]Instead of the contract being re-awarded to Remington, the Army awarded the contract for 120,000 M4A1 carbines worth $77 million toFN Herstalon 22 February 2013.[44][45]The order was expected to be completed by 2018.[46]

Replacement efforts

Replacements for the M4 have mostly focused on two factors: improving its reliability, and its penetration.[47]The first attempt to find a replacement for the M4 came in 1986, with theAdvanced Combat Rifleprogram, in which thecaselessHeckler & Koch G11and variousflechette rifleswere tested, but this was quickly dropped as these designs were mostly prototypes, which demonstrated a lack of reliability.[47]In the 1990s, theObjective Individual Combat Weaponcompetition was put forth to find a replacement for the M4. Two designs were produced, both byHeckler & Koch:theXM29 OICW,which incorporated asmartgrenade launcher, but was canceled in 2004 as it was too heavy, and theXM8,which was canceled in 2005 as it did not offer significant enough improvements over the M4.[47]

TheHeckler & Koch HK416was introduced in 2005, incorporating the same lower receiver as the M4A1, but replacing its direct impingement system with a gas-operated rotating bolt, more comparable to that of theG36.[48]The HK416 was adopted by theNavy SEALs,Delta Force,and other special forces.[47]In 2010, it was adopted by the Marines as the M27 Infantry Automatic Rifle.[49]The same year, theRangersand Navy SEALs adopted theFN SCAR,but later withdrew their purchase, as it was not a significant enough improvement over the M4A1.[50]

Individual Carbine

The U.S. Army briefly had a tender in 2011 called theIndividual Carbine,which solicited proposals for a potential M4 carbine replacement, but this was canceled in 2013 after determining that none of the entrants offered an adequate improvement over the M4.

For the Individual Carbine competition, Colt submitted theirEnhanced M4design, also known as theColt Advanced Piston Carbine(APC). 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".[51]In traditionalshort-stroke gas pistonoperating systems designed for the AR platform, 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 ascarrier tilt.The ALP 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.[52]The Individual Carbine competition was canceled before a winning weapon was chosen.[53]

Next Generation Squad Weapon

SIG SauerXM7,caliber6.8×51mm (.277 in)

After the failure of the Individual Carbine program, theNext Generation Squad Weapon(NGSW) was started in 2017. The program aimed to replace the M4 Carbine and the M249 SAW with weapons that would compensate for their perceived deficiencies when fighting at longer ranges, as well as addressing concerns about the effectiveness of traditional5.56x45mmammunition against troops wearingbody armorin a future peer or near-peer conflict. In order to achieve these goals, all weapon submissions were to be chambered in a new 6.8x51 mm caliber. SIG Sauer, Textron Systems, FN Herstal, True Velocity (previously Lonestar Future Weapons and General Dynamics), and PCP Tactical took part in the program. Textron submitted a cased-telescoped (CT) ammunition-firing rifle for the program; FN Herstal submitted theirHAMR IARre-chambered in 6.8mm caliber; PCP Tactical submitted a modifiedDesert Tech MDRx;SIG Sauer submitted a redesignedMCXvariant known as the MCX-SPEAR. In early 2022, the program concluded, withSIG Sauerbeing declared the winner. Their rifle entry was designated the XM5 (later changed toXM7to avoid confusion with the Colt M5),[54]and theXM250Squad Automatic Weapon.[55]Operational testing and fielding are scheduled for 2024.

Design

M4 withM68 Close Combat Opticand AN/PAQ-4

The M4, and its variants, is a lightweight5.56×45mm NATO(and.223 Remington) caliber, gas-operated, magazine-fed, air-cooled selective fire AR-15-patternfirearm.Its gas operation consists of an internal piston (often incorrectly referred to asdirect impingement),[56]a rotating bolt, and bolt carrier that reciprocates into a receiver extension that is inline with the barrel. The gas system, bolt carrier, and bolt-locking design is ammunition specific, since it does not have an adjustable gas port or valve to adjust the weapon to various propellant and projectile or barrel length specific pressure behavior. The receiver is made of forged 7075-T6 aluminum, while the 14.5 in (368 mm) barrel, bolt, bolt carrier, and fire control group are made of steel; these components can be easily serviced and replaced by unit armories, enabling the addition of enhanced components and thus making the platform readily upgradable. The flattop upper receiver's Picatinny rail enables the replacement of the removable carrying handle with various optics. The furniture, including the buttstock, grip, and handguard are made of reinforced plastic, although the modular nature of the weapon means that these can be swapped by the end user. The receiver extension can accommodate either a multi-positiontelescoping stockor a fixed A2 or LE tactical stock.[b][57]The M4 is a shorter and lighter variant of the M16A2 rifle, sharing much of the same operation mechanisms and has 80% parts commonality; the chief differences are a shorter barrel of 14.5 inches rather than 20 inches as well as a shortened receiver extension and buffer.[21][16]

Two fire control groups exist for the M4 family, the three-round burst for the baseline model and the fully automatic for the M4A1.[53]Some M4A1 may also have a heavier profile barrel initially developed for SOCOM for prolonged automatic fire; models with this heavier "SOCOM profile" barrel use the same M4A1 designation, and existing weapons can swap to the heavier profile barrel at the unit armory level. Despite being its namesake, SOCOM itself has reverted to the original lighter "government profile" barrel while adopting a longer "mid length" gas system with its newer Upper Receiver Group-Improved (URG-I) modifications. As the modifications only affect the upper receiver assembly, rifles with the URG-I still retain the M4A1 designation.[34]

M4 with the newer, redesigned telescopingstock

The M4's maneuverability makes it beneficial for non-infantry troops (vehicle crews, clerks and staff officers), as well as forclose quarters battle.The M4, along with the M16A4, has mostly replaced the M16A2 in the Army and Marines. TheU.S. Air Force,for example, has transitioned completely to the M4 for Security Forces squadrons, while other armed personnel retain the M16A2. The U.S. Navy uses M4A1s for Special Operations and vehicle crews. However, the M4's shorter barrel reduces its range, with its rear iron sights integrated in the (removable) carry handle only adjustable from 300 m (328 yd) up to 600 m (656 yd), compared to the M16A2 rear iron sights integrated in the fixed carry handle, which can reach up to 800 m (875 yd).[58]

Accessories

M4A1 just after firing, with an ejectedcasein mid-air; theM203andM68 CCOare attached

Like all the variants of the M16, the M4 and the M4A1 can be fitted with many accessories, such asslings,night-vision devices,flash suppressors,suppressors,laser sights,telescopic sights,bipods,M9 bayonet,either M203 or M320 grenade launcher, M26-MASS shotgun,forward hand grips,a detachable rail-mounted carrying handle, or anything else compatible with a MIL-STD-1913picatinny rail.[59]

Other common accessories include theAN/PEQ-2,AN/PEQ-15multi-mode laser,AN/PEQ-16 Mini Integrated Pointing Illumination Module (MIPIM),TrijiconTA01 and TA31Advanced Combat Optical Gunsights(ACOG),EOTech 550 seriesholographic sights, andAimpointM68 Close Combat Optic.Visible and infrared lights of various manufacturers are commonly attached using various mounting methods. As with all versions of the M16, the M4 accepts ablank-firing attachment(BFA) for training purposes.

The M4 and the M4A1 feed from 30-roundSTANAG magazines.[60]Other types of STANAG compatible magazines with different capacities may also be used. In January 2017, a USMC unit deployed with suppressors mounted to every infantry M4 service weapon. Exercises showed that having all weapons suppressed improved squad communication and surprise during engagements; disadvantages included additional heat and weight, increased maintenance, and the greater cost of equipping so many troops with the attachment.[61]In July 2020, the Marine Corps announced it would be ordering suppressors for use by all M4 carbines used by close combat units.[62]The Marines began to roll out suppressors for all M4/M4A1 carbines in infantry, reconnaissance and special operations units in December 2020.[63]

Special Operations Peculiar Modification

SOPMOD (Special Operations Peculiar Modification) Block I

In 1992,U.S. Special Operations Command(USSOCOM) developed the Special Operations Peculiar Modification (SOPMOD) Block I kit for the carbines used byUS Special Operations Forcesunits operating under its command.[64]The kit features an M4A1, a Rail Interface System (RIS) handguard developed byKnight's Armament Company(KAC), a shortened quick-detachable M203 grenade launcher andleaf sight,a KACsound suppressor,a KAC back-up rear sight, an Insight TechnologiesAN/PEQ-2A visible laser/infrareddesignator,along with Trijicon's ACOG TA-01NSN model andReflex sights,and anight visionsight, among many other accessories.[65]This kit was designed to be configurable (modular) for various missions, and the kit is currently in service with special operations units.[64]

SOPMOD Block II and Phased Replacements

In 2002, the Block II modification kit was adopted featuring two new upper receivers: the Special Purpose Receiver (SPR) with a 16 or 18 in (406 or 457 mm) barrel andClose Quarter Battle Receiver(CQBR) with a 10.3 in (262 mm) barrel.[66][67]M4A1s fitted with the SPR were designated by the Navy as theMk 12 Special Purpose Rifle,a type ofdesignated marksman rifle.[67]M4A1s with the CQBR were designated the Mk 18 Mod 0. The Block II program then focused on component improvements to the M4A1, with the adoption of the heavier "SOCOM profile" barrel in 2004 and free-float Rail Interface System II (RIS-II) handguard fromDaniel Defensein 2008. Owing to the modularity of the AR-15/M4 platform, some operators have replaced issued optics, handguards, and buttstocks with aftermarket ones.[67]

In 2018, the Upper Receiver Group-Improved (URG-I) modification kit (unofficially the Block III) was approved for the conversion of Block I and Block II carbine's upper receiver "to an improved barrel and rail assembly.." which includes a lighter free-float handguard from Geissele Automatics that incorporates theMagpul IndustriesM-LOKrail interface system. The URG-I also replaces the Block II's heavier barrel with a standard "government profile" cold hammer forged barrel with a longer gas system.[68]

Variants

The initial order of M4 carbines had a fixed carrying handle and rear sight similar to the M16A2. The flattop upper receiver with the Picatinny rail was introduced with the M4A1 variant in 1994, and all subsequent orders for all M4 variants would have a flattop upper receiver. Variants of the carbine built by different manufacturers are also in service with many other foreign special forces units, such as the AustralianSpecial Air Service Regiment(SASR). While the SASR uses weapons of essentially the same pattern built by Colt for export (Colt uses different models to separate weapons for the U.S. military and those for commercial/export purposes), the BritishSpecial Air Serviceuses a variant on the basic theme, theColt CanadaC8SFW.

M4 MWS (Modular Weapon System)

M4 MWS (Modular Weapon System) shown with various accessories includingM203 grenade launcher,RIS foregrip, removable carry handle/rear sight assembly, AN/PAQ-4laser system,M68 CCOreflex sight, and theAN/PVS-4night vision optics

Colt Model925carbines were tested and fitted with the KAC M4 RAS under the designationM4E2,but this designation appears to have been scrapped in favor of mounting this system to existing carbines without changing the designation. The U.S. Army Field Manual specifies for the Army that adding the Rail Adapter System (RAS) turns the weapon into theM4 MWSormodular weapon system.

M4A1

M4A1 with a carry handle
M4A1 withTA01NSN ACOG4×32 optical sight

The M4A1 carbine is a fully automatic variant of the basic M4 carbine. The M4A1 was developed in May 1991 and entered service in 1994; starting in 2014 the U.S. Army began upgrading all of its existing M4s to the M4A1 standard.[69]The M4A1 was the first M4 model with the removable carry handle. The M4A1 has a "S-1-F" (safe/semi-automatic/fully automatic) trigger group, while the M4 has a "S-1-3" (safe/semi-automatic/3-round burst) trigger group. The M4A1 is used by almost all U.S. special operation units; and is the standard service rifle across the U.S. Army (including conventional forces). It has a maximum effective range of 500 to 600 meters (550–660 yd).[5]The fully automatic trigger gives a more consistent trigger pull, which leads to better accuracy.[53]According to Mark Westrom, owner ofArmaLite, Inc.,automatic fire is better for clearing rooms than burst fire.[70]

A subvariant of the M4A1 uses a heavier barrel than the standard M4, as the regular M4 barrel, which can fire 6,000 rounds before requiring inspection for possible replacement,[20]was not sufficient for the higher consumption of ammunition by SOCOM operators.[38]The redesigned barrel, colloquially referred to as the "SOCOM barrel", has an increaseddiameterin the area between the receiver and front sight.[38]Despite the different barrel profile, this subvariant did not receive a new designation, and was still referred to as the M4A1. Ironically, SOCOM itself would dispense with its namesake heavier barrel and return to the original "government profile" with its Upper Receiver Group-Improved (URG-I) program's mid-length gassed, cold hammer forged barrels.[34][71]

Mk 18 CQBR

M4A1 lower receiver with a Mk 18 Close Quarter Battle Receiver upper. The barrel length is 10.3 in (260 mm)

TheClose Quarters Battle Receiver(CQBR) was originally a Special Operations Peculiar Modification (SOPMOD) program item that would increase the close quarters maneuverability of the M4A1 by mating the lower receiver with a 10.3-inch (262 mm) barreled upper receiver; with the CQBR installed, the weapon would then be classified as theMk. 18 CQBR.The Mk. 18 CQBR may be issued as a standalone complete weapon system to SOCOM personnel, or as a separate upper receiver for their M4A1 to enable greater mission flexibility.[72]

Mk 12 SPR

A Special Purpose Receiver built by NWSC Crane Division, mounted on an M16A1 lower receiver

The SOPMOD program also introduced theSpecial Purpose Receiver(SPR), a 16-or-18 in (406-or-457 mm) barreled upper receiver that would be mated to an M4A1 lower receiver to allow the weapon to serve as a designated marksman rifle (DMR). Although originally intended as an upper receiver kit for the M4A1 like the CQBR, the SPR would eventually be issued as a standalone complete rifle designated theMk. 12 Special Purpose Rifle,with some assembled from M4A1 lower receivers.

SOPMOD Block II

M4A1s in SOPMOD Block II used by 275th Ranger Regimentoperators clearing a room during a night raid inHelmand Province,Afghanistan, 2012

TheSOPMOD Block IIis a more radical modification kit for the baseline M4A1 that can be fitted at first-echelon unit maintenance level. Components of the Block II were phased in gradually, but the most distinctive feature is thefree-floatedDaniel Defense Rail Interface System II (RIS II), first issued in 2008. The RIS II is available in 9.5 inches for the Mk 18 Mod 1 or 12.5 inches for the M4A1. Other components of the Block II include the L3 Advanced Target Pointer Illuminator Aiming Laser (ATPIAL), or theAN/PEQ-15as well as the LA5 high-power variants, and the ELCAN SpecterDR 1-4 optic.

Upper Receiver Group-Improved (URG-I)

The URG-I used by one of theGreen Beretsfrom3rd SFG (A)with a black Magpul PMAG during training atMarine Corps Air Ground Combat Center,Twentynine Palms,Californiain 2019

TheUpper Receiver Group-Improved(URG-I) is aU.S. Army Special Operations Command(USASOC) program to further improve the durability and reliability of the SOPMOD Block II by introducing additional component improvements. First fielded in 2018, the main improvements are the lighter Geissele Mark 16 free-float rail that incorporatesM-LOKas the mounting method and a Daniel Defense cold hammer-forged barrel that returns to the lighter "government" profile contour as well as a mid-length gas system. Although initially an Army program, the URG-I has seen use by other components of SOCOM as well.

GAU-5/A

TheGAU-5/AAircrew Self Defense Weapon (ASDW) is an Air Force modified M4 with a detachable barrel and handguard assembly, folding pistol grip, and fold-down iron sights to enable compact packaging. This weapon is stowed inejection seatsof tactical aircraft and is intended to allowaircrewwho egress in hostile environments to better defend themselves until rescue than existing handguns. The weapons entered service in 2018.[73]Confusingly, this weapon shares the same designation as the Air ForceCAR-15variant in service since 1966.[74]

Performance

AU.S. Navy SEALwith an M4 during counterterrorism operations in Afghanistan, January 2002

The M4 carbine has been used for close quarters operations where theM16would be too long and bulky to use effectively. It has been a compact, light, customizable, and accurate weapon. Like other firearms, failure to properly maintain the M4 can result in malfunctions. This became apparent as it saw continued use in the sandy environments ofIraqandAfghanistan.[75]Despite this, in post-combat surveys, 94% of soldiers rated the M4 as an effective weapons system.[76]

2006 CNA report

In December 2006, theCenter for Naval Analyses(CNA) released a report on U.S. small arms in combat. The CNA conducted surveys on 2,608 troops returning from combat in Iraq and Afghanistan over the previous 12 months. Only troops who fired their weapons at enemy targets were allowed to participate. 917 troops were armed with M4 Carbines, making up 35% of the survey. 89% of M4 users reported they were satisfied with the weapon. 90% were satisfied with handling qualities such as handguards, size, and weight. M4 users had the highest levels of satisfaction with weapon performance, including 94% with accuracy, 92% with range, and 93% with rate of fire. Only 19% of M4 users reported a stoppage, and 82% of those that experienced a stoppage said it had little impact on their ability to clear the stoppage and re-engage their target. The lowest rated weapon was the M9, and theM249had the highest rate of stoppages.[77]53% of the M4 users never experienced failures of their magazines to feed. 81% did not need their rifles repaired while in theater. 80% were confident in the M4's reliability, defined as confidence their weapon will fire without malfunction, and 83% were confident in its durability, defined as confidence their weapon will not break or need repair. Both factors were attributed to high levels of soldiers performing their own maintenance. 54% of M4 users offered recommendations for improvements. 20% of requests were for greater bullet lethality, and 10% were for better quality magazines, as well as other minor recommendations. Only 75% of M16 users were satisfied with it,[78]and some expressed their desire to be issued the M4.[79]Some issues from this report have been addressed with the issuing of theimproved STANAG magazinein March 2009,[80][81]and theM855A1 Enhanced Performance Roundin June 2010.[82]

2007 dust test

In summer and fall 2007, the Army tested the M4 against three other carbines in "sandstormconditions "atAberdeen Proving Ground,Maryland:theHeckler & KochXM8,Fabrique Nationale de HerstalSOF Combat Assault Rifle(SCAR) and the Heckler & Koch HK416. Ten of each type of rifle were used to fire 6,000 rounds each, for a total of 60,000 rounds per rifle type.[83]The M4 suffered far more stoppages than its competitors: 882 stoppages, 19 requiring an armorer to fix. The XM8 had the fewest stoppages, 116 minor stoppages and 11 major ones, followed by the FN SCAR with 226 stoppages and the HK416 with 233.[84][85]

Despite 863 minor stoppages—termed "class one" stoppages, which require 10 seconds or less to clear, or "class two" stoppages, which require more than ten seconds to clear—the M4 functioned well, with over 98% of the 60,000 total rounds firing without a problem. The Army said it planned to improve the M4 with a newcold-hammer-forgedbarrel to give longer life and more reliable magazines to reduce the stoppages. Magazine failures caused 239 of the M4's failures. Army officials said the new magazines could be combat-ready by spring if testing went well.[86]The Army began issuing an improved STANAG magazine in March 2009.[80][81]

According to the Army, the M4 only suffered 296 stoppages and said that the high number reported could be attributed to discrepancies in the scoring process. The Army testing command stated that, if the number of stoppages caused by a broken part met some threshold, they would be eliminated from the final report pending redesign of the part. Themethodologyof the test has been debated, as many of the M4s in the test had already seen use, whereas the other rifles were brand new, and that the wide variance in results between summer and fall showed that the test was not accurate, as it was not repeatable with consistent results.[87]Furthermore, the trial M4s had burst-mode fire groups, which are more complicated and prone to failure than the fully automatic fire groups the other manufacturers presented for testing.[88]

There were three extreme dust tests performed in 2007. The second test results showed a large difference from the last test with the M4 having 148 class 1 stoppages caused by rifle malfunctions and 148 class 1 stoppages caused by magazine stoppages. The full-size M16 rifle had 61 stoppages during the same extreme dust test.[89]

Reliability

A U.S. Navy sailor fires an M4 carbine from the warshipUSSVella Gulf

In early 2010, two journalists from theNew York Timesspent three months with soldiers and Marines in Afghanistan. While there, they questioned around 100 infantrymen about the reliability of their M4 carbines, as well as the M16 rifle. Troops did not report reliability problems with their rifles. While only 100 troops were asked, they fought at least a dozen intense engagements inHelmand Province,where the ground is covered in fine powdered sand (called "moon dust" by troops) that can stick to firearms. Weapons were often dusty, wet, and covered in mud. Intense firefights lasted hours with several magazines being expended. Only one soldier reported a jam when his M16 was covered in mud after climbing out of acanal.The weapon was cleared and resumed firing with the next chambered round. Furthermore, a Marine chief warrant officer reported that there were no issues with hisbattalion's 700 M4s and 350 M16s.[90]

The reliability of the M4 has increased as the design was upgraded. In 1990, the M4 was required to fire 600 mean rounds between stoppages using M855 ammunition. In 2013, the current M4A1 version can fire 1,691 mean rounds between stoppages using M855A1 ammunition.[91]During the 2009 Marine Corps Infantry Automatic Rifle testing, the Colt IAR displayed a MRBS of CLASS I/II Stoppages of 952 rounds, with a MRBEFF (Mean Rounds Between Essential Function Failure) of Class III Stoppages of 60,000 rounds.[92]

Gas piston

An array of firearms accessory makers have offered gas piston conversion kits for the M4. The claimed benefits include less needed lubrication for thebolt carrier groupto run reliably and reduced fouling. The argument against it is increased weight and reduced accuracy.[93]The Enhanced M4 uses an articulating link piston operating system. Complicating the Army search for higher reliability in the M4 is a number of observations of M4 gas piston alternatives that suffer unintended design problems. The first is that many of the gas piston modifications for the M4 isolate the piston so that piston jams or related malfunction require the entire weapon be disassembled, such disassembly cannot be performed by the end-user and requires a qualified armorer to perform out of field, whereas almost any malfunction with the direct-impingement system can be fixed by the end-user in field. The second is that gas piston alternatives use an off-axis operation of the piston that can introduce carrier tilt, whereby the bolt carrier fails to enter the buffer tube at a straight angle, resulting in part wearing. This can also tilt the bolt during extraction, leading to increased bolt lug failures. The third is that the use of a sound suppressor results in hot gases entering the chamber, regardless of a direct-gas impingement or gas piston design choice. The gas piston system may also cause the firearm to become proprietary to the manufacturer, making modifications and changes with parts from other manufacturers difficult.[35][94]

Accuracy

In a study conducted by theArmy Marksmanship Unit,they found that at a distance of 300 yd (270 m), the M16 achieved a 24 in (610 mm)grouping,and the M4 achieved a 32 in (810 mm) grouping, which dropped to 12 in (300 mm) and 18 in (460 mm) respectively when usingmatch gradeammunition.[95]As the average male torso is 18–19 in (460–480 mm) wide, author Chris McNab concluded that this meant the M4 can be consistently accurate up to 300 yards, and noted that the frequent usage of optical attachments meant it could be accurate to higher ranges.[95]

ArmWest, LLC modified M4

In 2014, American firearms designerJim Sullivanprovided a video interview regarding his contributions to the M16 and M4 family of rifles while working for Armalite. A noted critic of the M4, he illustrates the deficiencies found in the rifle in its current configuration. In the video, he demonstrates his "ArmWest, LLC modified M4", with enhancements he believes necessary to rectify the issues with the weapon. Proprietary issues aside, the weapon is said to borrow features in his prior development, theUltimax.Sullivan has stated (without exact details as to how) the weapon can fire from the closed bolt in semi-automatic and switch to open bolt when firing in fully automatic, improving accuracy. The weight of the cyclic components of the gun has been doubled (while retaining the weapon's weight at less than 8 pounds). Compared to the standard M4, which in automatic fires 700–950 rounds a minute, the rate of fire of the ArmWest, LLC M4 is heavily reduced both to save ammunition and reduce barrel wear. The reduced rate also renders the weapon more controllable and accurate in automatic firing.[96]

Manufacturers

Trademark issues

The M4 was developed and produced for theUnited States governmentby Colt Firearms, which had an exclusive contract to produce the M4 family of weapons through 2011.[101]However, a number of other manufacturers offer M4-like firearms. Colt previously held a U.S.trademarkon the term "M4".[102]Many manufacturers offer production firearms that are essentially identical to a military M4, but with a 16-inch (41 cm) barrel. TheBushmaster M4 Type Carbineis a popular example. Civilian models are sometimes colloquially referred to as "M4gery" (/ɛmˈfɔːrəri/em-FOR-jə-ree,aportmanteauof "M4" and "forgery." )[103]Colt had maintained that it retained sole rights to the M4 name and design, while other manufacturers had long maintained that Colt had been overstating its rights, and that "M4" had now become a generic term for a shortened AR-15.[citation needed]

In April 2004, Colt filed a lawsuit against Heckler & Koch andBushmaster Firearms,claiming acts oftrademark infringement,trade dressinfringement,trademark dilution,false designation of origin,false advertising,patent infringement,unfair competition,and deceptive trade practices. Heckler & Koch later settled out of court, changing one product's name from "HK M4" to "HK416".However, on December 8, 2005, a district court judge inMainegranted asummary judgmentin favor of Bushmaster Firearms, dismissing all of Colt's claims except for false advertising. On the latter claim, Colt could not recover monetary damages. The court also ruled that "M4" was now a generic name and that Colt's trademark should be revoked.[103]

Users

A map with nations that use the M4 Carbine in blue

Former users

Conflicts

1990s

2000s

2010s

2020s

See also

References

Notes

  1. ^Magazines with different capacities also available
  2. ^The first stock fitted onto the M4 in 1985 was made entirely of plastic, which only had two positions; fully closed or fully extended. Later models have greater adjustability, and are commonly known as the "six position stock", "M4 stock", or, because of its recesses, "waffle stock".[16]

Citations

  1. ^Curtis, Rob (20 April 2012)."U.S. Army places order for 24,000 M4A1 carbines with Remington".Military Times.Archivedfrom the original on 24 June 2012.Retrieved23 August2012.
  2. ^Rottman 2011,p. 36.
  3. ^McNab 2021,p. 57.
  4. ^McNab 2021,p. 13.
  5. ^abcde"Operators Manual for Carbine, 5.56 MM, M4A1"(PDF).TM 9-1005-213-10.United States Army. June 2010. p. 18.Archived(PDF)from the original on 18 October 2022.Retrieved13 August2023.
  6. ^"M855A1 Enhanced Performance Round (EPR), LTC Philip Clark, Product Manager Small Caliber Ammunition, April 2012"(PDF).Archived fromthe original(PDF)on 25 January 2017.Retrieved25 February2017.
  7. ^"Small Arms–Individual Weapons"(PDF).Federation of American Scientists (FAS).3 November 2010.Archived(PDF)from the original on 9 February 2011.Retrieved8 November2010.
  8. ^"Marine grunts react to switch from the M16 to the M4".Marine Corps Times.1 November 2015.Archivedfrom the original on 25 April 2016.Retrieved4 February2023.
  9. ^abMcNab 2021,p. 5.
  10. ^McNab 2021,p. 6.
  11. ^"Army chooses Sig Sauer to build its Next Generation Squad Weapon".Army Times.19 April 2022.
  12. ^McNab 2021,p. 7.
  13. ^McNab 2021,p. 8.
  14. ^abMcNab 2021,p. 9.
  15. ^Hogg & Weeks 2000,p. 166.
  16. ^abcdefgMcNab 2021,p. 10.
  17. ^Rottman 2011,p. 43.
  18. ^McNab 2021,p. 14.
  19. ^McNab 2021,p. 46.
  20. ^abcdMcNab 2021,p. 47.
  21. ^abc"The Design & Development of the M-4 Carbine".Special Operations.com. Archived fromthe originalon 25 October 2008.Retrieved8 November2008.
  22. ^"Officers, staff NCOs to be issued M4s".Marine Corps Times. 25 June 2007. Archived fromthe originalon 18 December 2014 – via Leatherneck.com forums.Alt URL
  23. ^https://apps.dtic.mil/sti/tr/pdf/ADA500034.pdf
  24. ^"New Assignment Rationale for Individual Weapons".U.S. Marine Corps.22 June 2007. Archived fromthe originalon 29 November 2014.
  25. ^"M27 First Impressions".TheFirearmBlog.com.20 April 2013. Archived fromthe originalon 8 May 2013.
  26. ^"Corps exploring rifle upgrades".Military Times.29 April 2013. Archived fromthe originalon 1 May 2013.
  27. ^"Marine brass endorses infantry plan to ditch M16 for M4".Military Times.27 July 2015. Archived fromthe originalon 30 July 2015.
  28. ^"Commandant approves M4 as standard weapon for Marine infantry".Military Times.26 October 2015. Archived fromthe originalon 27 October 2015.
  29. ^"M27s and 'Head-to-Toe' Gear Overhaul on the Way for Marine Grunts".Military.com.5 January 2018. Archived fromthe originalon 7 January 2018.
  30. ^"Marine Raiders don't want any M27s".Marine Corps Times.19 February 2018. Archived fromthe originalon 24 February 2018.
  31. ^abCox, Matthew (7 July 2009)."Army acquires rights to M4".Army Times.Retrieved18 August2009.
  32. ^Stoner expanding gas patient
  33. ^Cox, Matthew (21 November 2009)."Major revamp possible for M4 carbine".Army Times.Archivedfrom the original on 18 July 2012.Retrieved21 November2009.
  34. ^abc"Request for Information (RFI)/Sources Sought – Upper Receiver Group – Improved (URG-I) Cold Hammer Forged (CHF) 11. 5" Carbine Length and 14. 5 "Mid-Length Barrels".Department of Defense.13 July 2020.
  35. ^abPannone, Mike (19 March 2010)."The Big M4 Myth:" Fouling caused by the direct impingement gas system makes the M4/M4A1 Carbine unreliable. "".Defensive Review.Archivedfrom the original on 14 August 2011.Retrieved27 July2011.
  36. ^"Dual Path Strategy: M4 PIP"(PDF).7 September 2011.Retrieved7 September2011.[dead link]
  37. ^Lamothe, Dan."Corps to pass on Army upgrades to M4".Marine Corps Times.Archived fromthe originalon 25 September 2010.Retrieved13 September2010.
  38. ^abcMcNab 2021,p. 16.
  39. ^"Beefier carbines en route to Soldiers".U.S. Army.22 May 2014. Archived fromthe originalon 3 September 2014.
  40. ^"Army infantry beginning adoption of upgraded M4A1 carbines".Guns.com.24 May 2014. Archived fromthe originalon 3 September 2014.
  41. ^"US Army Places Order For 24000 M4 Carbines With Remington".Military Times.Archived fromthe originalon 24 June 2012.Retrieved24 April2012.
  42. ^"Colt again blocks Army's advanced M4 plans".Military.com.18 October 2012. Archived fromthe originalon 27 September 2013.
  43. ^"GAO denies latest Colt M4 protest".Gearscout.com.Military Times. 28 November 2012. Archived fromthe originalon 1 December 2012.
  44. ^"Army Awards New M4/M4A1 Contract to FN".Military.com.23 February 2013. Archived fromthe originalon 26 February 2013.
  45. ^"FN Manufacturing Wins Contract to Supply M4A1".TheFireArmBlog.com.24 February 2013. Archived fromthe originalon 28 February 2013.
  46. ^"FN Manufacturing to deliver M4/M4A1 Carbines to US Army".Strategic Defense Intelligence.com.27 February 2013. Archived fromthe originalon 27 September 2013.
  47. ^abcdRottman 2011,p. 76.
  48. ^Moss, Matthew (19 March 2019)."Meet Heckler & Koch's HK416: The Rifle You Need To Know About".The National Interest.Retrieved4 July2021.
  49. ^Mizokami, Kyle (4 April 2017)."The Marines Are in the Market For Brand New Rifles".Popular Mechanics.Retrieved4 July2021.
  50. ^Rottman 2011,p. 77.
  51. ^"Enhanced M4".Defense Review.29 November 2011. Archived fromthe originalon 21 May 2012.
  52. ^"Colt's Advanced Piston Carbine, the LE6940P In Stores".InvestorVillage.com.Archived fromthe originalon 3 December 2013.
  53. ^abc"Army Kills Competition to Replace M4".Military.com.13 June 2013. Archived fromthe originalon 22 September 2013.
  54. ^South, Todd (18 January 2023)."New name selected for Army's Next Generation Squad Weapon".ArmyTimes.
  55. ^Beynon, Steve (19 April 2022)."Army Picks Its Replacement for the M4 and SAW".Military.com.Retrieved4 May2022.
  56. ^"AR-15 Direct Impingement vs Piston Gas Systems: What's the Difference? - CAT Outdoors".4 February 2024.Retrieved26 March2024.
  57. ^"Animation of the gas system of the M4 carbine".Militarytimes.com. Archived fromthe originalon 28 December 2009.Retrieved30 August2010.
  58. ^McNab 2021,p. 11.
  59. ^McNab 2021,pp. 22–28.
  60. ^McNab 2021,p. 66.
  61. ^"Marine Unit in Norway First to Deploy with Rifle Suppressors".Military.com.11 May 2017. Archived fromthe originalon 15 May 2017.
  62. ^The Marine Corps Plans on Fielding Suppressors to Infantry Squads Starting this Year.Military.com.13 July 2020.
  63. ^Marine Corps to start widespread distribution of suppressors.Marine Corps Times.31 December 2020.
  64. ^abMcNab 2021,p. 20.
  65. ^McNab 2021,p. 21.
  66. ^"1005-01-498-1913, Receiver, Automatic Gun".
  67. ^abcMcNab 2021,p. 29.
  68. ^"1005-01-671-3911, Modification Kit, Gun, Weapon".
  69. ^Moss, Matthew (20 March 2020).""US Army Continues M4 Modernization Program"".
  70. ^"Carbine Competition Fails to Find Improvement Over Current Weapon".National Defense Magazine.August 2013. Archived fromthe originalon 18 October 2015.
  71. ^"This new upper receiver is the closest you can get to owning one of USASOC's high-speed M4s".Military Times.3 October 2018.
  72. ^Johnson, Jeff."CQB Receiver – M4A1 Carbine with 10-Inch Upper Receiver"(Power point presentation).Scribd.com.US Naval Surface Warfare Center Crane.Archivedfrom the original on November 4, 2011.RetrievedMay 2,2012.
  73. ^Trevithick, Joseph (10 May 2019)."USAF Fighter Pilots Are Now Flying With These Converted M4 Rifles In Their Survival Kits".The War Zone.
  74. ^Trevithick, Joseph (5 June 2019)."USAF Fighter And Bomber Crews Get Modified M4 Rifles That Fit Under Ejection Seats".The War Zone.
  75. ^"M4 Carbine Controversy".Defense Industry Daily.Archived fromthe originalon 13 July 2007.
  76. ^"Small Arms-Individual Weapons"(PDF).Archived(PDF)from the original on 12 December 2017.Retrieved4 April2015.
  77. ^McNab 2021,p. 68.
  78. ^McNab 2021,p. 67.
  79. ^Russell, Sara M. (2006)."Soldier Perspectives on Small Arms in Combat"(PDF).CNA Corporation.Department of Defense. Archived fromthe original(PDF)on 31 August 2015.
  80. ^ab"Brownells shipping M16 magazines with anti-tilt follower to military".The Firearm Blog.13 June 2009. Archived fromthe originalon 21 September 2013.
  81. ^ab"New US Army M16" Tan "Magazine".The Firearm Blog.16 December 2009. Archived fromthe originalon 21 September 2013.
  82. ^"Army begins shipping improved 5.56mm cartridge".Picatinny Arsenal.24 June 2010. Archived fromthe originalon 1 June 2013.
  83. ^Lowe, Christian (18 December 2007)."M4 Carbine Fares Poorly in Dust Test".Military.com.Military Advantage.Archivedfrom the original on 13 August 2008.Retrieved13 September2008.
  84. ^"...And Here's the Rest of the M4 Story".Defense Tech.Military Advantage. 18 December 2007. Archived fromthe originalon 23 December 2007.Retrieved13 September2008.
  85. ^Cox, Matthew (19 December 2007)."Newer carbines outperform M4 in dust test".Army Times.Army Times Publishing Company. Archived fromthe originalon 30 June 2012.Retrieved24 July2019.
  86. ^Cox, Matthew (17 December 2007)."M4 may get tougher barrel, better mags".Army Times.Army Times Publishing Company. Archived fromthe originalon 21 July 2012.Retrieved24 July2019.
  87. ^McNab 2021,p. 73.
  88. ^"The Army's M4 Carbine: Background and Issues for Congress"(PDF).Fas.org.8 June 2010. Archived fromthe original(PDF)on 23 March 2015.
  89. ^Combat Tactics Fall 2008 Volume Six Number Two "True Grit" by David Crane
  90. ^Chivers, C.J. (July 7, 2010)."Examining the Complaints About American Rifle Reliability".The New York Times.Archivedfrom the original on September 22, 2013.
  91. ^Cox, Matthew (June 14, 2013)."Army: Gun Makers Didn't Meet Reliability Standard".Military.com.Archivedfrom the original on April 27, 2014.
  92. ^"USMC IAR Reliability Testing Results".Weaponsman.2009. Archived fromthe originalon April 12, 2017.
  93. ^"Best AR-15 Piston Uppers & Conversion Kits [2019]".Pew Pew Tactical.14 October 2017.
  94. ^"15259frcov.fm"(PDF).Archived fromthe original(PDF)on 31 August 2015.Retrieved30 August2010.
  95. ^abMcNab 2021,p. 37.
  96. ^"Interview & Shooting: Jim Sullivan, AR-15 Designer".Full30: INRANGE TV.26 November 2014. Archived fromthe originalon 28 February 2015.
  97. ^"R4 Complete System".Remington Defense.Archived fromthe originalon 14 December 2020.Retrieved18 February2021.
  98. ^"M4A1".FN America.Retrieved18 February2021.
  99. ^ab"Malaysia has licence to make M4 assault rifles".The Star.5 November 2007. Archived fromthe originalon 3 October 2008.Retrieved22 March2010.
  100. ^abcWatters, David."The 5.56 X 45mm: 2005".Archived fromthe originalon 7 August 2011.Retrieved10 March2010.
  101. ^"FindLaw's United States First Circuit case and opinions".Findlaw.Archivedfrom the original on 29 August 2016.Retrieved9 August2016.
  102. ^US Trademark serial number 76335060 registration number 2734001
  103. ^abRottman 2011,p. 75.
  104. ^Kelly, Tim (17 August 2021)."As Taliban takes over, some swap iconic AK-47s for made-in-America rifles".Reuters.
  105. ^"FOTOT/ Ushtria shqiptare tregon" dhëmbët "".Gazeta Tema.Archived fromthe originalon 23 December 2015.Retrieved6 January2016.
  106. ^abcdefghijklmnop"Colt Capitalizes on Foreign Military Sales Program - The Firearm Blog".27 April 2017. Archived fromthe originalon 1 June 2017.Retrieved1 May2017.
  107. ^"Clearance Divers, Maritime Tactical Operations".Australian Defence Jobs.Archived fromthe originalon 2 November 2010.Retrieved27 September2011.
  108. ^"DSX silahlanmasında ABŞ istehsalı tüfəng - M16 (ARAŞDIRMA)".
  109. ^abcdefghijklmWatters, Daniel."The 5.56 X 45mm: 2008".The Gun Zone. Archived fromthe originalon 4 January 2010.Retrieved27 January2009.
  110. ^abcdWatters, Daniel."The 5.56 X 45mm: 2006".Archived fromthe originalon 1 March 2011.Retrieved25 March2009.
  111. ^"wiw_sa_bolivia".worldinventory.24 November 2016. Archived from the original on 24 November 2016.Retrieved7 May2023.{{cite web}}:CS1 maint: bot: original URL status unknown (link)
  112. ^"PMERJ".Polícia Militar do Estado do Rio de Janeiro.Archived fromthe originalon 7 June 2014.
  113. ^"DOU 05/07/2012 - Pg. 28 - Seção 3 - Diário Oficial da União - Diários JusBrasil".JusBrasil.Archivedfrom the original on 29 November 2014.Retrieved15 November2014.
  114. ^"Croatian special forces with M4s".Archived fromthe originalon July 17, 2011.
  115. ^RUČNÍ ZBRANĚ AČR(PDF)(in Czech). Ministerstvo obrany České republiky AVIS. 18 April 2007.ISBN978-80-7278-388-5.Archived fromthe original(PDF)on 29 February 2012.
  116. ^"Nové útočné pušky pro české speciální síly".
  117. ^"Chinese Special Forces Competing With AR-15 Rifles".TheFirearmBlog.com.23 June 2013.Archivedfrom the original on 29 December 2018.Retrieved29 December2018.
  118. ^"Customers / Weapon users".Colt Defense Weapon Systems.Archived fromthe originalon 2 September 2011.
  119. ^"Soldiers from the Dominican Republic Special Forces fire the M4 Carbine rifle at targets down range at the shooting house in Sierra Piedras, Dominican Republic".nara.getarchive.net.20 April 2004.Archivedfrom the original on 9 February 2019.Retrieved7 February2019.
  120. ^"VBSS Rehearsals".DVIDS.Retrieved10 March2023.
  121. ^"World Infantry Weapons: Egypt".World Inventory.Archived fromthe originalon 12 March 2016.Retrieved26 January2018.
  122. ^abcWatters, Daniel."The 5.56 X 45mm: 2007".Archived fromthe originalon 10 October 2008.Retrieved25 March2009.
  123. ^Rottman 2011,p. 60.
  124. ^Sof, Eric (22 April 2017)."Colt wins multimillion contract to sell M4 Carbines to Georgia, Iraq".Archived fromthe originalon 22 July 2018.Retrieved3 June2018.
  125. ^"Georgia launches production of NATO standard GI-4 rifles".Rustavi2.ge.Rustavi2. 28 October 2021.Retrieved10 February2022.
  126. ^abcBinnie, Jeremy; de Cherisey, Erwan (2017)."New-model African armies"(PDF).Jane's. Archived fromthe original(PDF)on 22 June 2017.
  127. ^"34. Bercsény László Különleges Műveleti Zászlóalj"[Bercsény László 34th Special Operations Battalion]. Archived fromthe originalon 18 October 2017.Retrieved22 June2017.
  128. ^"Mizo cops to get foreign weapons".Meghalaya Times.June 13, 2010. Archived fromthe originalon October 9, 2011.RetrievedSeptember 27,2011.
  129. ^"Mizoram Armed Police".The Hindu.8 April 2009.Retrieved8 April2011.[dead link]
  130. ^Guerin, Bill (June 16, 2007)."Another success for Detachment 88".Asia Times Online. Archived from the original on February 2, 2009.RetrievedJanuary 20,2009.{{cite web}}:CS1 maint: unfit URL (link)
  131. ^"Kopassus & Kopaska – Specijalne Postrojbe Republike Indonezije"[Kopassus & Kopaska - Special Forces of the Republic of Indonesia] (in Croatian). Hrvatski Vojnik Magazine. Archived fromthe originalon 22 August 2010.Retrieved12 June2010.
  132. ^Giordono, Joseph (16 May 2007)."Iraqi soldiers switching over to M-16s and M-4s".Stars & Stripes.Archived fromthe originalon 1 August 2009.Retrieved25 March2009.
  133. ^CJSOTF-AP Public Affairs."U.S. Special Forces, Iraqi army ops: Raids result in 102 detainees, large weapons cache, no losses"(PDF).p. 8. Archived fromthe original(PDF)on 27 March 2009.Retrieved25 March2009.
  134. ^"'Delta Defence Group' Part Two: The Rifle ".silahreport.com.14 January 2020.Retrieved7 January2024.
  135. ^Watters, Daniel."The 5.56 X 45mm: 2000–2001".Archived fromthe originalon October 10, 2008.RetrievedMarch 25,2009.
  136. ^McNab 2021,p. 63-64.
  137. ^"Armi > Fucili d'Assalto > Colt M4"(in Italian). Archived fromthe originalon 22 July 2011.Retrieved18 July2010..colmoschin.it
  138. ^"Tomoaki Ishiba's statement"Toàn văn yết tái: Phạn sài đại úy の thanh minh văn(in Japanese). Archived fromthe originalon 2 February 2009.Retrieved12 January2009.
  139. ^"Lục thượng tự vệ đội đặc thù tác chiến quần | tự vệ đội thải dụng ガイド".jieitaisaiyou.web.fc2.com.Archived fromthe originalon 24 January 2016.Retrieved11 January2022.
  140. ^US Directorate of Defense Trade Controls. Notifications to the 108th Congress (November 2009)
  141. ^US Directorate of Defense Trade Controls. Notifications to the 108th Congress (November 2004)
  142. ^Christopher J. Castelli (September 2008)."Department of Defense to equip Lebanon's Special Forces with Small Arms, Vehicles"(PDF).DISAM Journal. Archived fromthe original(PDF)on 27 March 2009.Retrieved8 February2009.
  143. ^Thompson, Leroy (December 2008)."Malaysian Special Forces".Special Weapons. Archived fromthe originalon 30 December 2009.Retrieved17 December2009.
  144. ^Bazza, Tarek (21 September 2018)."Morocco's Military Buys US M4 Carbine Rifles and Navy Systems".Morocco World News.Retrieved29 December2021.
  145. ^"Colt to Supply 10,000 M4, M4A1 Carbine Rifles to Pakistan, Afghanistan, Morocco".Defense World.net.21 September 2018. Archived fromthe originalon 29 December 2021.Retrieved29 December2021.
  146. ^"Legacies of War in the Company of Peace: Firearms in Nepal"(PDF).Nepal Issue Brief(2).Small Arms Survey:5. May 2013. Archived fromthe original(PDF)on 8 July 2014.Retrieved8 January2019.
  147. ^"Unofficial New Zealand Special Air Service page".Archivedfrom the original on 12 November 2004.Retrieved25 March2009.
  148. ^"Split second decisions: police rules of engagement".The Sunday Star-Times.1 February 2009.Archivedfrom the original on 12 October 2012.Retrieved15 October2011.
  149. ^"Replacement due for police rifles".New Zealand Police.19 May 2005.Archivedfrom the original on 8 March 2016.Retrieved8 March2016.
  150. ^"US gifts North Macedonia Colt M4 rifles".3 March 2021.
  151. ^"Pakistan Army".Archived fromthe originalon 13 May 2013.
  152. ^"U.S. Army Weapon Systems Handbook 2012"(PDF).Archived(PDF)from the original on 12 December 2017.Retrieved25 April2013.
  153. ^Adnan Abu Amer (10 May 2015)."Security services drain Palestine's budget".Al-Monitor. Archived fromthe originalon 5 May 2017.Retrieved8 June2017.
  154. ^ab"Peruvian Small Arms: Gunning for the Shining Path".Small Arms Defense Journal.3(3).Retrieved26 October2022.
  155. ^"Philippine Army acquires R4 carbines".Archived fromthe originalon 29 March 2014.Retrieved15 November2014.
  156. ^"US-based Remington wins bid to supply 50,000 M4 rifles for AFP, company rep says".Interaksyon.com. Archived fromthe originalon 6 May 2013.Retrieved4 May2013.
  157. ^"Small Arms Repair and Upgrade Unit".Bullet-in.June 2015.
  158. ^Sebastian Miernik."Uzbrojenie i wyposażenie"[Armaments and equipment] (in Polish). Grom.mil.pl. Archived fromthe originalon 14 August 2011.Retrieved30 August2010.
  159. ^"Спецподразделение" Группа "Альфа" ФСБ РФ. История, с иллюстрациями "(in Russian). Archived fromthe originalon 10 December 2016.
  160. ^"FRIENDSHIP-2020 ~ Joint Russian-Pakistani SOF Exercise".Joint Forces News.11 November 2020. Archived fromthe originalon 30 January 2024.Retrieved30 January2024.
  161. ^"Senegal received 2 200 M4 carbines from the US".defenceWeb.26 July 2019.
  162. ^"Moderan" gradski "karabin"[A modern "city" carbine] (in Serbian). Kalibar.rs.Archivedfrom the original on 27 February 2012.Retrieved30 August2010.
  163. ^"Singapurske Specijalne Postrojbe"[Singapore Special Forces] (in Croatian). Hrvatski Vojnik Magazine. Archived fromthe originalon 15 October 2009.Retrieved25 October2009.
  164. ^McNab 2021,p. 60.
  165. ^"Bình đông huyện cảnh sát cục bảo an đội trang bị giới thiệu"[Equipment introduction].Ptpolice.gov.tw(in Chinese). 29 January 2007. Archived fromthe originalon 18 May 2008.Retrieved27 September2011.
  166. ^"Colt contracted for M4, M4A1 rifles for foreign military sales".UPI.Archivedfrom the original on 21 September 2018.Retrieved21 September2018.
  167. ^"International Glocks: Fighting Terror in Tunisia".Tactical Life.18 March 2016.
  168. ^Tracker, Ukraine Weapons [@UAWeapons] (14 May 2022)."#Ukraine: Unpacking a pristine American M4A1 carbine by a Ukrainian soldier. Approximately 7000 small arms (including M4A1 rifles) were recently donated to Ukraine by the United States as military aid"(Tweet).Archivedfrom the original on 31 May 2022.Retrieved20 May2022– viaTwitter.
  169. ^Watters, Daniel."The 5.56 X 45mm: 1990–1994".Archived fromthe originalon January 4, 2010.RetrievedMarch 25,2009.
  170. ^abHogg, Ian (12 November 2002).Jane's Guns Recognition Guide(3rd ed.). Collins Reference.ISBN000712760X.
  171. ^Petty Officer First Class David Votroubek (July–August 2008)."New Gear for Afghan Commandos".United States Army Logistics Management College.Archived fromthe originalon 1 August 2009.Retrieved24 March2009.
  172. ^Soraya Sarhaddi Nelson (23 July 2007)."New Afghan Commandos Take to the Frontlines".National Public Radio.Archivedfrom the original on 2 August 2009.Retrieved24 March2009.
  173. ^Noir, War."#Jammu & #Kashmir: A member of" Kashmir Tigers "(KT) was reportedly killed by Indian Forces during the clashes in #Doda".x.com.Retrieved26 June2024.
  174. ^"How Did American Weapons End Up at Donetsk Airport?".bellingcat.19 January 2015.Retrieved14 January2021.
  175. ^"El atentado más cruel del EPP en 19 años - Notas - ABC Color".www.abc.com.py(in Spanish).Retrieved21 April2021.
  176. ^abSnow, Shawn (7 May 2017)."Syrian Kurds are now armed with sensitive US weaponry, and the Pentagon denies supplying it".Military Times.Archivedfrom the original on 22 April 2019.Retrieved22 April2019.
  177. ^"Intruders photo in Sabah".Sabah Daily(in Malay). Archived fromthe originalon 6 March 2013.Retrieved2 March2013.
  178. ^"Arming the Maute Group in Marawi City".The Firearm Blog.22 June 2017.Archivedfrom the original on 14 November 2017.Retrieved23 November2017.
  179. ^"Photos: Clashes in Beirut near protest against blast probe judge".aljazeera.com.Retrieved12 May2022.
  180. ^Tracker, Ukraine Weapons [@UAWeapons] (6 June 2022)."#Ukraine: A collection of a few of the weapons currently used by Ukrainian army: FN F2000 Tactical and M4A1 assault rifles + Beretta M9 and Glock 19 Gen 5, donated by allies.Classic Soviet Tokarev and Stechkin APS pistols + a modded AKS-74U are also seen"(Tweet).Archivedfrom the original on 9 August 2022.Retrieved13 August2022– viaTwitter.
  181. ^"From India to Israel, US weapons being used to attack its allies".indiatoday.in, 11 October 2023
  182. ^"At least 64 killed in 'largest' tribal clashes in Papua New Guinea".Al Jazeera.Retrieved19 February2024.

Bibliography