THE LINE between life and death is sliver thin on Corlies Street.

It was 4:45 on a November afternoon in 2008 when Alicia Colter stood up from the computer in her dining room and took a few steps toward the kitchen to start dinner. She stopped and turned when her then-8-year-old twins summoned her to the living room to watch something on TV.

That very instant, a .380 bullet exploded through the dining-room window and whizzed by, six inches from her skull. If Colter hadn't veered, the bullet, which lodged in the kitchen wall, likely would have struck her.

"My children called me away and they saved my life," Colter said. "If I'd been in the kitchen, I'd be brain dead or gone."

In this street-war shootout between two young, angry men in Grays Ferry, another bullet pierced the siding of a house across the street. In all, detectives found seven casings - two from a .380 semiautomatic pistol.

The same pistol was used in eight shootings between June and December 2008 in a small segment of Grays Ferry. There are plenty more neighborhoods just like it.

The city's streets are saturated with illegal guns that mostly teenagers and young men buy - or rent - easier and faster than a $10 bag of marijuana.

"You have a glut of guns that are out there and they fall into the hands of criminals," Police Commissioner Charles Ramsey said in a recent interview.

"People are buying them on the street and they pass through many hands. So there's no guarantee when a gun is used in multiple shootings that it's even fired by the same person."

In 2011, the Bureau of Alcohol, Tobacco, Firearms and Explosives traced 4,157 guns that were recovered in Philadelphia. Almost 200 fewer weapons were confiscated in New York City, even though it has about 6.7 million more people.

"Everybody out there who's involved [in crime] knows where to get a gun," said Donald Robinson, assistant special agent in charge of ATF's Philadelphia division, "whether it's [acquired in] burglaries or thefts or just buying off of someone you know."

About 86 percent of the city's 331 homicides in 2012 were by gun, as opposed to 56 percent of the 419 killings in New York City.

Roots of the crisis

Philly's gun problem has multiple causes:

* Illegal guns are so plentiful that it takes less than half an hour for teens or young men to buy or borrow one. Once it's been used in a shooting, it is considered "hot" and is passed on to someone else.

* Carrying an illegal gun is not considered a serious crime under state law. In fact, it's a misdemeanor. There is no mandatory-minimum sentence.

"To carry a gun without a license in Philadelphia has historically almost been a joke," said District Attorney Seth Williams.

* The city doesn't have the resources to saturate gun trouble spots with police officers and keep them there long term.

* The Police Department's controversial stop-and-frisk policy was the subject of a 2010 class-action lawsuit charging that minorities were targeted and stops were sometimes made without probable cause. The city agreed to procedural changes, but civil-rights groups argue that many stops are still made without reasonable suspicion.

For the past year, the District Attorney's Office has worked to get tough on gun offenses.

Williams has pushed for dramatically higher bails and stiffer, mandatory sentences for people charged with illegal gun possession.

"Gun violence is the biggest problem facing our criminal-justice system and jeopardizing public safety in Philadelphia," Williams said.

People like Alicia Colter who live within the Grays Ferry blocks of 26th to 31st streets and Wharton to Tasker know all too well. They wonder when - not if - the next homicide will happen.

Last year, 13 people were robbed at gunpoint there; 14 people were shot and three more were slain, one of them a mother of five caught in the cross-fire between two gun-toting men.

"So many of them around here are packing," said Colter, 57, who works as a drug- and alcohol-abuse counselor.

"I try to talk to them about not retaliating, that there's a better way out," she said. "I tell them to stop killing their own people.

"Some people tell me to mind my own business. But if I get hurt helping, so be it."

No 'straws' needed

It's a myth that most of Philly's illegal guns are driven up from the South and sold out of car trunks along with cellphones and knock-off purses and sunglasses.

Of the 9,591 firearms that ATF recovered and traced in Pennsylvania in 2011, 53 percent were homegrown, first purchased legally in the Keystone State.

Federal, state and local authorities have successfully cracked down on straw purchasers. "Straws" - as they are called - are gun buyers who have no criminal record. Felons, who can't buy guns legally, hire straws to do it for them. Frequently, the straw then reports the gun stolen to avoid criminal responsibility when it's used in a crime.

Philadelphia's Gun Violence Task Force has arrested 822 people for straw purchasing or other gun-trafficking offenses since its 2006 inception. At least 342 of them have been convicted.

But because there are so many guns on Philly's streets, criminals don't need straw purchasers.

Street thugs also know that even if a crime gun is recovered, tracing it can be challenging - if not impossible. On average, 11 years pass from when a weapon is legally purchased to when police recover it after a crime. By then, countless people could have owned the gun.

To further snag investigators, criminals have become savvy at obliterating weapons' serial numbers.

"Phantom guns," investigators call them.

Take the case of the .380 used in eight shootings in seven months in that slice of Grays Ferry.

In December 2008, police found the pistol in the hands of Aquil Atwell, then 18, a member of the 27th Street gang who was warring with the 31st Street gang.

Atwell was cocky about his thuggish ways. At 5-feet 11-inches, 155 pounds, Atwell had a tattoo of a "2" in the shape of a gun on his left arm and a bullet-riddled number "7" on his right.

Atwell was accused of using the .380 to shoot Ricky Moore - an alleged 31st Street gang member - in the foot on Dec. 11, 2008.

Detectives had found shell casings from that gun in seven other shootings in the previous six months, including a shootout on Aug. 18, 2008, that left Atwell with a bullet wound to his left arm.

Because half the serial number had been removed from the .380, investigators were unable to trace the gun. It remains in the police department's evidence room at City Hall.

Charges against Atwell in the Moore shooting were dismissed. Atwell's attorney argued that police did not have cause to search him when officers found the gun.

Moore told police he was unable to identify the man who shot him.

Investigators couldn't tie the other shootings to Atwell either.

But Atwell would not go unarmed for long.

In July 2011, police stopped him after he ran a stop sign and he was charged with driving under the influence. At the time, he was on probation for a drug case.

A .40-caliber handgun, loaded with nine rounds, one in the chamber, was on the floor behind the passenger's seat of the Buick he was driving.

Atwell is now serving a 2 1/2- to 5-year sentence for that weapons offense. Investigators attempted to trace the gun but found nothing.

One more Philly phantom gun.

Need tougher penalties

There is little fear of jail time for gun offenses in Philadelphia.

"The way to change behavior is to have more swift and certain consequences, which have certainly lacked in Philadelphia," said First Assistant District Attorney Ed McCann.

"We have to ensure that when you carry a gun, you're going to get some jail time," he said. "It has to be taken seriously."

The D.A.'s office has made strides on that front. In November and December 2012, the average bail for illegal gun possession was $152,000, compared to just $18,750 during the same period in 2011.

During that same period in 2012, 69 percent of suspects who were charged with weapons violations received jail time, compared to 53 percent a year earlier, said Tasha Jamerson, a D.A. spokeswoman.

Defendants convicted of weapons violations also saw the length of their average sentences increase to 2- to-4 1/2 years, from 1.6- to-3.6-years, Jamerson said.

"If you know you can't carry a gun with impunity, it's a deterrent," said Bryan Lentz, who heads Philly's Gun Violence Task Force.

There has to be a gun fear factor, experts say.

"When you are caught with an illegal gun, there has to be consequences," said Mark Kleiman, a professor who studies crime policy at the University of California, Los Angeles.

Williams told the Daily News that he is lobbying Harrisburg to make illegal-gun possession a third-degree felony, punishable by a mandatory-minimum of two years in prison.

"The people of this city need to know that if you carry illegal guns and do crimes with guns, we're coming after you hard and furious," Williams said.

Williams said he wants a message on billboards: "If you carry, you do two."

'It's hell'

Back on Corlies Street, Alicia Colter and her partner, Nannette Johnson, stay on high alert, especially when their twins, Aaliyah and Nigel, head home from school.

Aaliyah, who attends Independence Charter School, and Nigel, at Masterman, take separate buses and walk home.

"It's scary when a bullet flies through the window," Aaliyah said. "It's like you always have to be cautious of what's happening and pay attention to everything. When I was little, I'd like to play outside, but it was difficult . . . because sometimes shooting would start up down the street."

Three years ago, Colter saw a young man who'd been gunned down at 31st and Tasker.

"His brains were on the ground," she said.

"It's not normal to sit around your neighborhood and hear shooting. But it happens. You start to sleep through it," she said.

Last April 20, she rushed down Corlies Street when she heard screams and shots half a block away. She found Clarice Douglas, 45, a mother of five, lying on her back on the concrete porch.

"I'll never forget it. Her eyes were just blank. And there was blood everywhere," Colter said.

Douglas was a bystander, shot when a gun battle erupted near her house. Two men were arrested; one hanged himself with a T-shirt in a holding cell.

Douglas had lived on the block since the 1990s and cared for her ailing mother and children.

The house is empty now. Douglas' mother couldn't live with the memory of losing her only child, so she moved in with a relative miles away.

She told a Daily News reporter that she was still too distraught to talk.

Douglas' daughter, Anesa Newell, 22, was a college sophomore in Maryland when her mom was killed.

She came back to Philly and takes care of her brother, Savion, 12, and sister, Bryonna, 9, in a Philadelphia neighborhood far from Grays Ferry.

Anesa works at the YMCA, goes to community college and cleans houses for extra money.

"That neighborhood was horrible," she said in a recent interview. "You never knew when someone was going to start arguing and you never knew if they were carrying. I always feared that something like that would happen."

Bryonna and Savion don't talk much about the day their mom was killed.

"It's hell," Anesa said.

"It's just not fair," Bryonna told her recently. "I'm 8 years old and I don't have my mom.

"She's not coming back."

- Staff writer Dana DiFilippo contributed to this report.

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