M16 rifle

The M16 (officially Rifle, Caliber 5.56 mm, M16) is a family of <a href="/facts/Assault_rifle/H2DXHauQ">assault rifles</a>, chambered for the <a href="/facts/5.56%25C3%259745mm_NATO/eT9ENFzY">5.56×45mm NATO</a> cartridge with a 20-round magazine adapted from the <a href="/facts/ArmaLite_AR-15/m9Glo8c5">ArmaLite AR-15</a> family of rifles for the <a href="/facts/United_States_Armed_Forces/NHVsU9Id">United States military</a>. 
In 1964, the XM16E1 entered US military service as the M16 and in the following year was deployed for <a href="/facts/Jungle_warfare/P0x43CRk">jungle warfare</a> operations during the <a href="/facts/Vietnam_War/W0gfbGTE">Vietnam War</a>. In 1969, the M16A1 replaced the <a href="/facts/M14_rifle/VXfIjJkh">M14 rifle</a> to become the US military's standard service rifle. The M16A1 incorporated numerous modifications including a bolt-assist ("forward-assist"), chrome-plated bore, protective reinforcement around the magazine release, and revised flash hider.
In 1983, the <a href="/facts/United_States_Marine_Corps/J8JDlJG2">US Marine Corps</a> adopted the M16A2 rifle, and the <a href="/facts/United_States_Army/WACWBEK9">US Army</a> adopted it in 1986. The M16A2 fires the improved 5.56×45mm (M855/SS109) cartridge and has a newer adjustable rear sight, case deflector, heavy barrel, improved <a href="/facts/Handguard/pwf8ahFw">handguard</a>, pistol grip, and <a href="/facts/Buttstock/PgD8ochN">buttstock</a>, as well as a semi-auto and three-round burst fire selector. Adopted in July 1997, the M16A4 is the fourth generation of the M16 series. It is equipped with a removable carrying handle and quad <a href="/facts/Picatinny_rail/ujtT0Mq7">Picatinny rail</a> for mounting optics and other ancillary devices.
The M16 has also been widely adopted by other armed forces around the world. Total worldwide production of M16s is approximately 8 million, making it the most-produced firearm of its 5.56 mm caliber. The US military has largely replaced the M16 in frontline combat units with a shorter and lighter version, the <a href="/facts/M4_carbine/ncoafLmS">M4 carbine</a>. In April 2022, the U.S. Army selected the <a href="/facts/SIG_MCX_Spear/AvatvUYC">SIG MCX SPEAR</a> as the winner of the <a href="/facts/Next_Generation_Squad_Weapon_Program/WJqvw04B">Next Generation Squad Weapon Program</a> to replace the M16/M4. The new rifle is designated <a href="/facts/M7_rifle/JgluFuXk">M7</a>.

M16 rifle open-in-new

M16 rifle