The history of this iconic American weapon, from its inception in 1959 to the present day.
smallwarsjournal.com
"General Curtis LeMay saw a demonstration of the AR-15 in 1960. Impressed by the prowess of this new firearm, when General LeMay became the Air Force Chief of Staff in the Summer of 1961, he placed 80,000 AR-15's on order for the U.S. Air Force.
In 1961, ten AR-15's were sent to South Vietnam, as the United States continued to penetrate into the jungles of Indochina."
"The Difference Between the AR-15 and the M16
So, what are the differences between the AR-15 and the M16? Are they the same thing? One of the easiest ways to think about this is that every M16 is an AR-15; however, not all AR-15s are an M16. At the basic level, the M16 is a fully automatic rifle. The AR-15 a semi-automatic only. At the same time, remember that the original AR-15 was fully automatic. It was made semi-automatic for civilian purposes.
Ultimately, the M16 uses the foundation of the AR-15 and modifies it slightly. The AR-15 is primarily seen today as the foundation of all other semi-automatic rifles and automatic rifles that the military uses to this day. The M16 was created with a few modifications from the basic AR-15 design to make it more useful for the military’s purposes.
In addition, the AR-15 was also modified slightly for civilian purposes. The lower receiver of the AR-15 does not have a third trigger pinhole for the safety selector. The trigger pocket is also mailed slightly differently to accommodate for this change. Those who look closely at the M16 and AR-15 might notice these differences."