(Corrects day of week in second paragraph, Thursday not Tuesday)
* Biggest gunfight with federal agents in U.S. history
* 12,000 rounds fired in 1993 raid on Texas cult
* Lessons learned: more medical care, firepower, planning
By Ian Simpson
WASHINGTON, Feb 8 (Reuters) - A splintering storm of gunfire through walls and the floor was one former ATF agent's searing memory of the deadly raid on the Branch Davidian compound near Waco, Texas, 20 years ago this month.
Bill Buford, who helped plan the raid that turned into the biggest gunfight with federal officers in U.S. history, said late on Thursday he and other Bureau of Alcohol, Tobacco, Firearms and Explosives agents had expected a normal day in law enforcement, not a 12,000-round firefight with a heavily armed apocalyptic cult.
"We were going to go in there, we were going to kick a little bootie, then we were going to ease out and be home before noon. It didn't work out that way," Buford, joined by other retired ATF agents involved in the Waco raid, told a gathering hosted by the National Law Enforcement Museum and Target Corp .
The fighting erupted on Feb. 28, 1993, when ATF agents attempted to execute a search warrant on the Branch Davidian compound and its leader David Koresh. Four ATF agents were killed and 16 were wounded, and five Davidians died.
An ensuing 51-day siege by the Federal Bureau of Investigation ended when the FBI fired tear gas into the compound. A few hours later, the building burst into flames and most of those inside died. The FBI says Koresh and other cult members set the fires rather than surrender.
Buford, joined by retired agents Jerry Petrilli and Pete Mastin, said the ATF raid began with agents immediately coming under fire from M-60 machine guns, AK-47 assault rifles and .50-caliber weapons fired by the tipped-off Davidians.
"I was quite concerned, you might say," said Buford, who was the resident agent in charge of the Little Rock, Arkansas, ATF office.
He and agents Keith Constantino and Glen Jordan climbed onto a roof to get into the compound's armory on the second story.
Along with Jordan, he broke the gun room window. Buford tossed in a flash grenade when he saw a Davidian inside with an AK-47, and the team entered the room, which had 35 or 40 guns and a box of grenades.
The Davidian then re-entered the room "and I was able to neutralize him," Buford said without elaborating.
"By this time we were receiving fire through all the walls. The only Davidian I saw that day was the one individual. But the gunfire was intense coming through the walls," he said.
Jordan was struck in the back. Bleeding heavily, he yelled he had been hit.
"We were still receiving a tremendous amount of gunfire through the walls. I can remember holding on to a two-by-four which was part of the gun rack and the splinters coming off from the rounds hitting it were kicking in my face, and (I) was having trouble figuring out why I wasn't being hit."
Buford said he knelt down to help Jordan while firing blindly through the walls.
"They started shooting through the floor, and the first round hit me ... right in the back end. That one wasn't too bad," he said.
Jordan yelled he had been hit again. Buford said he himself was then wounded again by an AK-47, once in the hip and once in the thigh.
"The rounds were still coming through the walls. I remember trying to push up off the floor and get out of there," he said, adding that he was scared a stray round might hit the box of grenades and blow it up.
With Constantino covering for them, Jordan and Buford got out the window. Buford rolled off the roof, breaking several ribs. As a medic worked on him, he was hit a fourth time, this time in the face.
Constantino was badly injured in a fall from the roof.
A subsequent Treasury Department investigation said the ATF raid was badly mishandled and should have been called off after supervisors learned that Koresh knew it was coming.
Mastin, who was the special agent in charge of the ATF's New Orleans office, called the raid "a bitter pill to swallow."
Buford, Mastin and Petrilli, who had been the ATF's resident agent in Albuquerque, New Mexico, said the ATF raid suffered from lack of firepower, intelligence and operational security and no contingency plan for getting out if it went wrong.
Lessons from the failed raid have led to sharp improvements in medical care, training, planning and the increased use of snipers, they said.
ATF Director Todd Jones told the audience that experience gained in the Waco shootout had meant only one agent had died since then.
ATF agents "were heroes that day, in my mind, and that bravery continues. It's in the DNA of the ATF," he said. (Reporting by Ian Simpson; Editing by Paul Thomasch and Nick Zieminski)