Any able-bodied resident of this town of 5,700 who doesn't have a gun to call his own today became a criminal in the eyes of the law.

The law is a three-paragraph city ordinance requiring a gun in every home, and ammunition in every gun. Violators face a $200 fine and up to 60 days in jail.

It went into effect today as men raced up and down Main Street in pickups shouting, "Where's yer gun?" at reporters.

Mayor Darvin Purdy, 38, a lawyer and National Rifle Association member who owns several guns of undisclosed caliber ("the caliber of my weapons is a personal matter") says the law is necessary to send criminals a message that they rape and pillage in Kennesaw at grave risk.

Not that there has been much rape or pillaging in this historic Civil War town, 24 miles north of Atlanta. Still, it has remained vigilant ever since Union commando James J. Andrews and his raiders stole a Confederate locomotive, the General, in 1862, while its conductor was eating breakfast, and set off to burn rebel bridges.

He was later caught and shot, after an 87-mile high-speed chase re-created in the movies, and any criminal who tries to pull off such a caper nowadays risks the same fate, some locals say.

Little old ladies pack the Kennesaw police pistol range alongside workmen from Lockheed to learn how to fire their first gun. They hound officers like Dwayne Wilson, an instructor, with the kind of questions lawyers hesitate to answer: just when can you shoot an assailant and go free?

"We tell 'em, 'If you're afraid he'll do you bodily harm, pull the trigger and take your chances with 12 ladies and gentlemen of the jury,' " Wilson said.

They take aim at the "X" plastered on life-size targets, and if they can hit the paper man from 21 to 45 feet, Wilson says he figures they can hit a burglar in a darkened bedroom.

Some have signed up for the 10 free guns the mayor has promised to give away, all gifts from out-of-town admirers who wanted to make sure Kennesaw had enough firepower to go around.

They needn't fret.

"This may be a town of only 5,000 people, but there must be at least 50,000 guns," said carpet salesman Jerry Lyn, 43, a former paratrooper in Vietnam who dropped into Lawson's Texaco to fill up, swap war stories and talk about his favorite guns.

"Everybody's for the gun ordinance except kooks," said Lee Lawson, 60, the gas station owner. "It's a good thing to let criminals know you're ready for 'em." He grinned and told about the night he chased a carload of drunks from his back yard with 15 quick shots from a .30-cal. carbine.

"They drove into my yard whoopin' and hollerin', and I yelled, 'You're on private property.' They cussed me out and kept partying. So I bounced a few shots off the brick wall. They tore up their cars getting off my place."

He said he doesn't think he'd have the heart to kill anyone: he'd give a robber a fair chance to put up his hands.

But some say the forced arms buildup is dangerous. Retired police officer Bill Prince, 44, said he thinks that more guns in the home means more people will shoot each other.

"Someone gets mad, first thing he does is grab a gun. I've seen husbands and wives threaten each other, 'You were out with so and so, I'll blow your brains out.' Always talked 'em out of it, but there are plenty who pull the trigger," he said.

Even Robert Carrier, 21, a $5-an-hour county employe who plunked down $35 for a .38 special to comply with the law, calls it "ridiculous, just another stupid law. You got little kids in the house, you're just inviting trouble."

The American Civil Liberties Union sought an injunction today in federal court in Atlanta to halt the law. And up the road in Acworth, the City Council passed a parody ordinance requiring all households to own fishing poles.

Mayor Purdy says he doesn't think it's funny. Last year there were 55 burglaries. Since the ordinance was passed, almost three months ago, there have been three. And Purdy says police will not be above checking shotgun racks on routine house calls, to enforce compliance. Those who refuse to have a firearm could face arrest. Convicted felons, the disabled and conscientious objectors are excused.

Not that a law was needed. About 9 out of 10 households already owned guns before the City Council passed the controversial ordinance as a response to a Morton Grove, Ill., (nicknamed "Moron Grove" here) statute banning handguns.

A country tune, "Kennesaw Get Your Guns," is spinning on local stations. It is a song by Jimmy Moore, a plumber who says "Every issue ought to have a song you can dance to." And merchants like Dent Myers, 51, are prospering, selling souvenir Ku Klux Klan robes, Kennesaw T-shirts and $2 citizenship papers to tourists.

"This is just a nice, easygoing town with a silent majority and a pioneer spirit," he said.