West Hartford, Connecticut (CNN) -- The sign at the door of the Colt factory displays a gun with a slash through it: "No loaded or unauthorized firearms beyond this point." Understandable for workers at a plant, but also a bit ironic, considering one of the largest arsenals in America lies just beyond.
Inside, a cacophony of clinks and clanks, the whir of aluminum being forged and the rattle of robotics echo through the 300,000-square-foot facility.
Hundreds of employees work round-the-clock to assemble iconic Colt handguns, machine guns for the U.S. military and the AR-15 rifle for civilians -- the weapon at the heart of the gun debate.
The factory is an impressive tribute to a lost art in America, a booming manufacturing hub at a time when many corporations are shipping jobs overseas. Colt's 670 workers cover three shifts, six days a week.
Colt has invested millions of dollars to modernize the facility and keep up with demand. All major components are made inside these walls. Smaller parts come mostly from suppliers within a 50-mile radius.
The plant is divided in two. One side is dedicated to making handguns, the other to military weapons and the AR-15.
As I walked through one area, dozens upon dozens of M240s -- belt-fed machine guns that can fire 950 rounds a minute -- were being made for members of the U.S. military. An American flag hung at a nearby station.
"We all here have a great responsibility to build a gun that someone's son, daughter, father, or mother will use not only in defense of our country, but in the defense of their lives," a sign said. "Failure is not an option."
Not too far away, gray-haired grandmas and rugged blue-collar men put together AR-15s in an assembly line. Each gun is test-fired at least 40 times in the plant's indoor gun range.
The factory is not too different from any other. But here the product is not blue jeans, computers or an automobile.
It's an item whose use is enshrined in the Constitution. Yet it's also one that has come under scrutiny as technology has made guns more deadly -- and as more of them seem to end up in the hands of killers.
In the months since the December 14 massacre of 20 children and six adults at Sandy Hook Elementary School, a very public war has been waged pitting those seeking gun control against the gun industry and gun rights advocates.
"Working at Colt, we're very proud of what we do here," said John Sgueglia, the director of quality engineering. "We just hope we can continue what we're doing."
Where the Second Amendment is sacred
I came to Colt after spending a week in Newtown talking with residents there, including many strong supporters of gun control.
As someone who has hunted since age 10, I wondered what it was like to make guns less than 50 miles from the site of the massacre in a state that has become increasingly hostile toward its gun manufacturers.
Colt has a rich 175-year history in Connecticut. Its original main factory, topped by a blue onion dome with gold stars, has been designated a national historic site in Hartford. An effort is under way to make the mid-19th century building part of a national historic park, a move that has drawn some backlash in the wake of Newtown.
The current factory, in West Hartford, sits in what is known as New England's Gun Valley, a corridor along the Connecticut River that dates back to the American Revolution with the Springfield Armory in Massachusetts. The gun trade here flourished during the expansion of the Western frontier, with gun makers establishing roots in Connecticut and Massachusetts and stretching northward to New Hampshire.
To this day, gun makers like Colt, Smith & Wesson, Sturm Ruger and Stag Arms continue to proliferate in the valley.
With billions of dollars and thousands of jobs at stake, what better place to visit than the heart of America's gun-making industry? What might workers here have to say about the tragedy of Newtown and the current gun debate?
The massacre at Sandy Hook was so sickening, Colt Manufacturing CEO Dennis Veilleux told me, that calling it a crime "doesn't sound like strong enough of a word." He's a father of two boys, including one named Jesse -- a name shared with one of the first graders gunned down inside the school.
"You automatically put yourself in the situation of those parents and their children, and it cuts you to the core," he said. "It hurts you."
But making guns is also big business.
The decade-long wars in Afghanistan and Iraq offered a booming business for Colt Defense, the company's military branch, as hundreds of thousands of M240s, M249 light machine guns and M4 carbines were produced for the U.S. military.
That demand carried over to its civilian market, according to industry experts, as military veterans returned home seeking semi-automatic rifles like the AR-15 for target shooting, home defense and hunting.
Just last year, Colt made 100,000 AR-15s, dubbed sporting rifles by the industry and assault rifles by critics. The privately held company expects bustling sales again this year as gun owners and collectors snatch them up ahead of any potential bans.
"It is the single most popular semi-automatic rifle in the United States," said Veilleux (pronounced vay-YOU).
Touring the facility and talking with employees, it became clear the Second Amendment is sacred here. They don't just say that as a cliché to be repeated to a reporter. It's real, they say, a right guaranteed in the Constitution that should not be infringed.
Veilleux pointed to a stack of letters from gun owners. He gets about 500 a week. "You need to stand up for our Second Amendment rights as much as you can," one man wrote.
Added Veilleux: "I believe in the Second Amendment."
Colt's ties with the AR-15 date back to 1959 when it bought the rights from ArmaLite, a company that made the lightweight 6-pound rifle in hopes of securing a defense contract. The gun was designed to pierce both sides of an armored helmet from about 500 yards away.
Colt would win a military contract by 1962, and the fully automatic version of the rifle was designated as the M16, which would become the standard-issue service rifle during the Vietnam War.
A civilian version of the rifle was introduced by Colt in 1964. That gun, like today's model, was a semi-automatic, meaning a shooter has to pull the trigger to fire a shot; the military version spits out round after round with a single trigger pull. The designation AR-15 stands for the gun's original platform, ArmaLite Rifle 15.
Today, gun manufacturers and industry groups stand by the AR-15 and say they're simply making a product the public wants.
But in 1989, Colt executives decided to stop making them after the AR-15 became the gun of choice among drug gangs. "We sense a great concern on the part of the government toward the possible inappropriate misuse of semi-automatic weapons," then-Colt spokesman Michael Dunn told The New York Times. "We're responding to that concern."
William Bennett, then head of the nation's drug policy under President George H.W. Bush, called the decision "an active civic responsibility" and said he was "confident that our country is better for it."
The decision didn't last, though. A year later, under new leadership, Colt began making AR-15s again.
In his office, Veilleux emphasized the strongly held belief by gun advocates that the weapon used in Newtown -- a .223-caliber Bushmaster, which is built on the AR-15 platform -- was not the issue. The problem was that it fell into the hands of mentally troubled Adam Lanza.
"The product was used because we weren't able as a society to keep that out of the hands of somebody that shouldn't have had it," he said. "We weren't able to get ahead of it. We weren't able to see it coming."
Banning the weapon might make "great headlines," Veilleux said, but it won't "make a difference in terms of making society safer."
A refusal to compromise
Don't get Connecticut Gov. Dannel Malloy started. He was in the Sandy Hook firehouse December 14 and delivered the news to the 26 families gathered there that their loved ones were killed inside the nearby school.
The tragedy touched him deeply, and he has staked his political career on taking on the gun industry in the months since.
"What this is about is the ability of the gun industry to sell as many guns to as many people as possible, even if they're deranged, even if they're mentally ill, even if they have a criminal background," he told CNN's Candy Crowley in early April. "They don't care. They want to sell guns."
He chastised NRA Executive Vice President Wayne LaPierre as a "circus clown," and he blasted the gun industry for its refusal to compromise -- not even on universal background checks for all gun purchases, which polls show has the support of about 90% of Americans.
"Of course, there are things we can agree on," Malloy said, "but they can't agree on anything that has to do with guns. That's the problem."
Malloy recently signed into law some of the strictest gun measures in the nation, including one that requires background checks on all gun purchases and the addition of more than 100 weapons to the state's list of banned assault weapons. The industry has filed suit to block the law.
In his interview on CNN, he said gun manufacturers were welcome to stay in the state. "But you know what," he said, "we've decided that the public's safety, that schoolchildren's safety, that schoolteacher's safety, trumps all of that."
More than 32,000 Americans die every year from gun violence, the majority from suicides, according to data from the Centers for Disease Control and Prevention. Spree shootings account for a tiny fraction of the overall violence.
The National Sports Shooting Foundation, a lobbying arm of the gun industry based in Newtown, estimates 1.3 million sporting rifles are made in America every year. The group says a federal ban on those rifles and other semi-automatic shotguns could lead to a loss of 26,000 manufacturing jobs and cost nearly half a billion dollars in lost federal and state taxes.
In early March, more than 500 Colt employees were bused to the state legislature in Hartford to rally against banning weapons.
"Save our jobs," they chanted.
Garen Wintemute, a professor of emergency room medicine at UC-Davis who has campaigned for stronger gun regulations and studied the New England Gun Valley for more than 30 years, said gun makers and their employees genuinely mean it when they say they "don't want their guns to be used to kill innocent people."
"On the one hand, they can be aghast and they can grieve like we all did after Newtown," he said. "On the other hand, their primary obligation in a professional sense is to move product.
"Neither they nor any other consumer product industry has ever voluntarily seen some broad responsibility to the public that outweighs their narrow responsibility to shareholders."
As gun violence continues to rip at the core of American society, Wintemute said, "The key question is not 'Do you abhor the use of your products in crimes?' The key question is, 'What are you going to do about it?'"
He paused and added, "Their answer is, 'Absolutely nothing.'"
'We're wasting time'
Veilleux was thrust into the position of Colt Manufacturing CEO in January after his predecessor, former Marine Lt. Gen. William Keys, retired in the weeks after the massacre in Newtown. Colt says Keys' decision to step aside was unrelated to the shooting spree. He remains on the company's board.
Veilleux stepped in at a most difficult time, with his industry coming under fire. He joined Colt in 2006 from U.S. Repeating Arms -- maker of Winchester guns -- and quickly rose through the executive ranks.
He has a cocked eyebrow similar to Stephen King's and jokes that it makes him look angry all the time. His office has a secure gun safe containing an array of weapons from Colt and its competitors. A couple of empty rifle cases lie about amid heaps of paperwork.
When it comes to gun control, he chooses his words deliberately and thoughtfully. Being new to the job allows him to "really evaluate what's best for us as a company and as a citizen of the community and the country."
There are more troubled people in America like Adam Lanza, he said; little is being done on the mental health front to help them, and they could very well end up with a weapon.
"We're wasting time talking about cosmetic features of guns and things of the like," he said, "instead of concentrating as a society on what we need to do to get a handle on the risks associated with this type of behavior."
The nation's leaders, he said, need to "work on how we deal with desensitizing (gun violence), how we deal with mental illness, how we deal with criminals, what we do with people when they commit crimes."
But wouldn't measures like universal background checks or limiting magazines to 10 rounds help minimize the risks of guns falling into the wrong hands?
Not according to Veilleux, who opposes both.
Instead, he would prefer to see improvements to the current National Instant Criminal Background Check System. He would like for gun dealers to have better access to mental health records and criminal backgrounds.
"We actually have a system that works. We need to build on that," he said. "We need to take that system, hold people accountable to use it and build on it."
Currently the system gives dealers a straight yes or no as to whether someone can purchase a weapon, with no supplemental detail about a buyer's mental health or potential criminal record. However, improving that system would not close the current loophole that allows a person to buy weapons at gun shows with no check at all.
Veilleux also said prosecutors need to crack down on what's known as "straw purchases," when a third party is used to buy a gun for a criminal. "Don't sell them to criminals. If you do that, you need to go to jail. You need to be punished."
What non-gun owners don't understand, Veilleux said, is the vast majority of Americans who bear arms take that right seriously and detest those who misuse guns. "They don't represent a gun owner any more than a drunk driver who kills someone represents a car manufacturer."
As he adjusts to his new role, Veilleux hears it from all sides. Gun control advocates want Colt and other manufacturers to become more responsive, and gun enthusiasts don't want him to relent.
Every time Gov. Malloy opens his mouth, more letters pour in, urging Colt to bolt. Texas and Mississippi are among the states that have courted the company to move out of Connecticut.
"Our first choice is to continue to work and build here," he said. "But our customers will not buy our products made and distributed from a state that doesn't respect their Second Amendment rights."
Malloy has downplayed the possibility of gun manufacturers leaving the state, but the threats to leave are real. PTR Industries, a maker of military-style rifles, became the first Connecticut gun maker in recent months to announce it is moving.
"The rights of the citizens of Connecticut have been trampled upon," PTR Industries said in April. "With a heavy heart but a clear mind, we have been forced to decide that our business can no longer survive in Connecticut -- the former Constitution state."
An engraver's art
Michael Guerra, Colt's product marketing manager, showed me a Colt Competition AR-15 along with a more traditional Remington hunting rifle. A bullet shot from both guns travels at 3,100 feet per second, nearly four times the speed of a Colt .45 handgun.
He ran through a demonstration on how to cock and load both. He explained that bullets fired from older versions of the AR-15 used to tumble in the air toward a target. That has been fixed in the modern guns. The bullet spins without tumbling at 3,000 RPMs.
He called the school shooting in Newtown "one of the most awful things we have ever seen."
"But really my response is we can load this gun, put the safety off, leave it in this room and walk away, and it's not going to get up and shoot anybody," Guerra said. "These guns don't just go out and shoot people -- either of them. There's safe and responsible gun ownership and that's what we really need to focus on."
What does he think of limiting a magazine to 10 rounds from 30, like Adam Lanza used?
"You know, if somebody wanted to wreak havoc, they would just have more 10 rounders and have to reload quicker. That's all."
Inside the factory's custom shop, George Spring chiseled away. A master engraver who has worked for Colt since 1975, Spring has custom designed guns for people ranging from presidents to Hollywood stars to janitors.
At least one of his guns, with intricate gold inlays, fetched $150,000. Others have gone for $40,000. Near his work station is what he described as the only engraved Colt Gatling gun in the world. He and one of his fellow engravers spent 100 hours on it, carving the Colt onion dome onto the barrel. It's value: more than $60,000.
Unlike the mass-produced guns on the factory line, his guns should never be fired. "If you do shoot the gun, you're actually going to take value off of it," Spring said.
The blunt-spoken engraver has strong feelings on the right to bear arms -- and on the factory that has provided his way of life for decades. The idea of Colt leaving Connecticut, he said, is a bit ridiculous.
"It's all political. Every bit of it."
Yet he took part in the protest at the state legislature in March as a show of solidarity for his colleagues.
A Vietnam veteran, Spring grew up in nearby Essex. Back then, a shooting club met after school on Tuesdays. On those mornings, he'd hop on the school bus with his .22-caliber rifle.
"Now, if you took a rifle on a school bus, I don't even want to think of what would happen," he said. "The world has definitely changed."
Like many here, he bristles when people refer to the AR-15 as an assault rifle. "Any weapon that you pick up and assault somebody with is an assault weapon. I don't care if it's a typewriter or a chair or a table," he said.
"If the AR-15 was responsible for Sandy Hook, then airplanes are responsible for the World Trade Center. Isn't that one and the same?" he said. "It's the people that do it, not the guns."
Out on the factory floor, workers sealed bags containing AR-15s and prepared them for shipment. I thought about what Colt CEO Veilleux had told me.
"That product when used by responsible citizens is not a danger to society," he said. "The problem is we need to concentrate on what we can do to keep that product out of the hands of the people who shouldn't have it."
Yet how best to do that remains elusive. Until then, the factory will keep making the weapons. On this day, hundreds more AR-15s were assembled, put in boxes and readied for delivery.