The M16A1 incorporated fixes to the original M16's reliability problems, including a chrome-lined bore and chamber, forward assist, birdcage flash suppressor, and issued cleaning kit. It became the standard US infantry rifle through the Vietnam era and into the 1980s. Type: Semi-Auto Rifle Action: Gas-Operated Caliber: 5.56x45mm Capacity: 20 Year introduced: 1967, USA Weight: 7.9 oz Overall length: 39.5" Status: Discontinued Military use: Yes Intended use: Military, Service Rifle