Back in the 1980s, I wrote a long detailed article about the design concepts that the AR-15's creator, Eugene Stoner, put into this weapon, and the ways it changed before going into service as the military’s M-16.

A half-century later, AR-15s and M-16s are made in varied forms by multiple manufacturers, and updated versions, including the M-4 carbine, remain the standard shoulder-fired weapon for most American service members and many allies.
Civilian versions have many trade and model names, but are generally referred to as AR-15s, although this name is a rough description and does not indicate whether a particular specimen of the rifle is capable of both semiautomatic fire and automatic fire, or is semiautomatic only.

The main functional difference between the military’s M16 and M4 rifles and a civilian AR-15 is the “burst” mode on many military models, which allow three rounds to be fired with one trigger pull. Some military versions of the rifles have a full automatic feature, which fires until the trigger is released or a magazine is empty of ammunition.
But in actual American combat these technical differences are less significant than they seem. For decades the American military has trained its conventional troops to fire their M4s and M16s in the semiautomatic mode — one bullet per trigger pull — instead of on “burst” or automatic in almost all shooting situations. The weapons are more accurate this way, and thus more lethal.
The National Rifle Association and other pro-gun groups highlight the fully automatic feature in military M4s and M16s. But the American military, after a long experience with fully automatic M16s reaching back to Vietnam, decided by the 1980s to issue M16s, and later M4s, to most conventional troops without the fully automatic function, and to train them to fire in a more controlled fashion.
What all of this means is that the Parkland gunman, in practical terms, had the same rifle firepower as an American grunt using a standard infantry rifle in the standard way...
A New York Times analysis of a video from a Florida classroom estimates that during his crime the gunman fired his AR-15 as quickly as one-and-a-half rounds per second. The military trains soldiers to fire at a sustained rate of 12 to 15 rounds per minute, or a round every four or five seconds.

A few years ago, the family of the inventor of the AR-15 said he would have been horrified to know that its design was being used to slaughter children and other innocent lives instead of being used as a military weapon on the battlefields, as it was designed — that’s what it was designed for. Enough. Enough.

ArmaLite was an infant and an upstart, a company that began as a workshop in the Hollywood garage of George Sullivan, the patent counsel for Lockheed Aircraft Corporation. Sullivan was an engineer fascinated with the possibilities of applying new materials to change the way rifles looked and felt. In 1953, he met Paul Cleaveland, secretary of the Fairchild Engine and Airplane Corporation, at an industry luncheon. The pair talked about lightweight firearms and new ways to manufacture them. Cleaveland mentioned the conversation to Richard Boutelle, Fairchild's president, who was a gun buff, too. Boutelle and Sullivan agreed to collaborate, and ArmaLite was founded in 1954 as a tiny Fairchild division. It hired a former Marine, Eugene Stoner, as a designer.
One of the early creations was the AR-15, made at the informal request of an Army general who wanted a prototype rifle that would fire a small, high-speed round. The AR-15 looked like nothing else in military service. It had an aluminum receiver, plastic furniture, and an odd-looking carrying handle. It was thirty-nine inches long. It weighed, when unloaded, roughly 6.5 pounds, about half the weight of an automatic M14. Its appearance — small, dark, lean, and synthetically futuristic — stirred emotions. To its champions, the AR-15 was an embodiment of fresh thinking. Critics saw an ugly toy. Wherever one stood, no one denied the ballistics were intriguing. Stoner had designed a narrow but powerful new cartridge, the .223, for his weapon. The cartridge's propellant and the AR-15's twenty-inch barrel worked together to move a tiny bullet along at ultrafast speeds — in excess of thirty-two hundred feet per second, almost three times the speed of sound.

The AR-15 is, essentially, a gun that was designed to inflict maximum casualties, death, and injury, in close to medium range. That's what it does. The real problem is that we allow that kind of firepower to come into a theater or into a first-grade class. The names you see now are 'modern sporting rifle,' 'tactical rifle.' Those are all just euphemisms for 'assault weapon.' They're being very rational as marketers and as businesses—and as industries. They're only doing what cellphone companies do to make cellphones look different and be more attractive. The difference is what they're selling is lethality.

Classified reports from Vietnam were giving the AR-15 high marks and providing a surprise. Reports from the field claimed that when a bullet fired from the AR-15 struck a man, it inflicted devastating injuries.
The causes were apparently twofold. First, the metal jacket of early AR-15 bullets tended to shatter on impact, sending fragmentation slicing through victims. (In the army, this was variously seen as attractive and worrisome. In classified correspondence, some officers were thrilled by the perceived wounding characteristics, which one prominent army doctor described as "explosive effects." Others wondered whether the .223 round might be illegal under international convention.) Second, the bullets often turned sideways inside a victim, a phenomenon known as yaw. In one respect, the effects of yaw somewhat resemble what could be seen on the surface of a lake when a speedboat turned sharply. In this case, the energy delivery manifested itself as a shock wave within a human body, which could create stretching or rupturing injury to tissue not directly in a bullet's path. By turning, the bullet also crushed and cut more tissue as it passed through a victim, creating a larger wound channel.

I spent a career carrying typically either an M16 or an M4 Carbine. An M4 Carbine fires a .223 caliber round which is 5.56mm at about 3000 feet per second. When it hits a human body, the effects are devastating. It’s designed for that. That’s what our soldiers ought to carry. I personally don’t think there’s any need for that kind of weaponry on the streets and particularly around the schools in America.

The Bushmaster a variant of a type of gun called the AR-15 ... which was designed and developed for military use roughly during the Vietnam War period. It is one of a variety of assault rifles that militaries of the world developed when they realized that most soldiers do not — when they're engaged in combat — do not take accurate aim, do not fire at long distances, but rather just spray bullets in the general direction of the enemy at short to medium range. When the military accepted this as a fact — that soldiers are not marksmen, and they tend to just fire in bursts at ambiguous targets, and in fact most battlefield injuries are the result of just being where the bullet is and not someone actually aiming at you — the militaries of the world said, 'OK, we need a type of gun to give our soldiers that will do just that.' ... This was the genesis of the assault rifle. The first one was developed by the Germans in 1944. It was called the StG-44. The Soviet army quickly ... made a design similar to it, which is called the AK-47, probably the most widely used rifle in the world.

Among the six deadliest mass shootings in the last six years, the only one not carried out with an AR-15 style rifle was the Orlando nightclub attack two years ago that left 49 dead. The gunman, Omar Mateen, had a Sig Sauer MCX semiautomatic rifle, which shares features with the AR-15, though it functions via a different semiautomatic design — and is just as deadly. All of these military-style semiautomatic weapons have something else in common. They have been heavily marketed as home-defense and marksmanship weapons, and their sales have been a major driver of profits for gun manufacturers over the past two decades.

Many factors determine the severity of a wound, including a bullet’s mass, velocity and composition, and where it strikes. The AR-15, like the M4 and M16 rifles issued to American soldiers, shoots lightweight, high-speed bullets that can cause grievous bone and soft tissue wounds, in part by turning sideways, or “yawing,” when they hit a person. Surgeons say the weapons produce the same sort of horrific injuries seen on battlefields.
Civilian owners of military-style weapons can also buy soft-nosed or hollow-point ammunition, often used for hunting, that lacks a full metal jacket and can expand and fragment on impact. Such bullets, which can cause wider wound channels, are proscribed in most military use.

Americans who know nothing else about firearms are all too familiar with the name AR-15. It’s the semi-automatic weapon that murderers have used in many of the most notorious and highest-casualty gun killings of recent years: Aurora, Colorado. Newtown, Connecticut. Orlando, Florida. San Bernardino, California. Now, with modified versions, in Las Vegas, Nevada, and Sutherland Springs, Texas.

Our nation mourns once again a horrific loss of life that should be unthinkable, yet is becoming routine. Assault weapons, like the AR-15 style weapon used in yesterday’s attack, are military bred firearms designed for a specific purpose: to kill as many people as possible in as short an amount of time as available. Mass shooters utilize guns like the AR-15 because of their specific anti-personnel design characteristics. We cannot talk about effective solutions to stopping these types of attacks without addressing the tools that make them possible. Until assault weapons and high-capacity ammunition magazines are banned, these attacks will continue to threaten our public life and define our nation.

The Draeger could be dangerous at depths much below thirty feet, so Juan planned to stay close to the surface. In a slim waterproof pouch strapped under his right arm he had a minicomputer, a flashlight, and a Fabrique Nationale Five-seveN double-action automatic. The pistol fired the new 5.7mm ammunition. The advantage of the small, needlelike cartridges was that the matte-black weapon's grip held twenty rounds with one in the chamber. Also, the bullets were designed to blow through most ballistic vests while at the same time not overpenetrate a target.