Carpet bombs won't pick off an urban sniper. A tank isn't much use in an alley. In a Baghdad battle, handguns and high-powered assault rifles would be vital -- along with some decidedly low-tech weapons like a shotgun, bulldozer or pick ax.

With special operations forces working inside Baghdad on Friday -- their submachine guns and 9 mm SigSauer pistols probably equipped with silencers -- weapons specialists underscored the gritty and risky nature of urban combat.

"At some point it just becomes who's the better shot and who's got the most bullets to shoot," said retired Lt. Col. Tim Eads, a weapons expert who served with Army special forces and the mechanized 24th Infantry Division -- later reorganized into the 3rd Infantry Division that is now outside Baghdad.

Weapons most effective in urban settings are not necessarily the multimillion dollar fighter jets, bombers and helicopter gunships coalition forces have used outside Baghdad. Helicopters are vulnerable to small arms fire, and air power isn't much use to an infantry fighting from buildings.

And, while air support would undoubtedly play a role in a Baghdad battle, experts don't expect to see troops parachuting into the city.

"It's too risky," Eads said. "You're not going to drop guys in on top of buildings. The casualties would be staggering."

Instead, urban combatants rely on close-range weapons and tactics used by SWAT teams, city police and firefighters, especially when it's desirable to minimize civilian casualties -- Baghdad has a population of 5 million -- and widespread destruction.

Troops trained for urban fighting are told to expect "confused melees" demanding precision small-arms fire and "moment-to-moment decisions by individual soldiers," according to the Army's urban warfare manual.

"We're not going to see tank-on-tank battles," said Peter W. Singer, a defense analyst at the Brookings Institution. "You're going to need to get infantry into those areas."

The U.S. infantry carries the M16 assault rifle or the M4, a newer, shorter variation. Like the Iraqis' counterpart -- the AK-47 -- the M16 can deliver rapid bursts of automatic fire.

The M16 has a superior sighting system: Hitting a target is a matter of simply lining up two dots and firing or, at night, projecting the dot onto a target and pulling the trigger. AK-47 operators must manually line up a target in the sights.

And, it is easier for an M16 operator to shift from safety to semiautomatic mode, which allows for greater accuracy than the long bursts of automatic fire more typical of how Iraqi soldiers use the AK-47, Eads said.

Some U.S. troops carry M16s with an attachment that fires 40 mm grenades, effective in taking buildings or other close-in targets. Other grenades in the U.S. arsenal deliver blasts of smoke, phosphorus or explosive noise designed to confuse, blind or stun, a tactic used by SWAT teams in hostage situations.

While U.S. weapons are superior to those wielded by the Iraqis, the Army's urban warfare manual concedes that "U.S. technological advantages are often not very useful during" urban operations.

For example: The U.S. military's main battle tank, the M1A1 Abrams, has greater range, firepower and armored protection than Iraq's older, Soviet-built T-72, T-62 and T-55 tanks, and Baghdad's wide main avenues would give the massive vehicles plenty of maneuvering room.

But long-range capability doesn't help much in close combat on city streets -- the Army says 90 percent of urban targets are engaged at a distance of only 50 yards -- or in narrow areas.

More useful is the Bradley fighting vehicle, a lighter-armored vehicle with a shotgun and assault rifle that can be fitted with a grenade launcher. The guns are on a stabilizing turret that adjusts with the vehicle's movement to keep on target.

The Iraqi counterpart, the older Soviet-designed BMP fighting vehicle, doesn't make such an adjustment, weapons experts said.

Singer said U.S. urban combat weapons include pick axes and shovels to rip open doors, ropes with grappling hooks, and explosives to punch through walls. Combat engineers would move in to destroy key targets and infrastructure, perhaps using bulldozers as Israel did in the siege of the Jenin refugee camp last year.

Protective equipment like knee and elbow pads, heavy gloves and special eyewear is important but can cost troops the mobility that is important in urban combat. And coalition forces would need every edge to defeat a hidden enemy defending its home turf, said Christopher Hillman, senior analyst at the Center for Defense Information.

"I don't think the advantage is ever to the aggressor in a situation like this," he said.