TAMPA -- Behind showcases of Magnum .357s, pearl-handled pistols and long-barreled rifles, plus the bullets to load this arsenal, Lauren Pidgeon of Pidgeon's Gun Supply portrayed himself as both a gun dealer and gun enthusiast. No one doubts it. His enthusiasm recently extended to children.

For $125, Pidgeon took out a full-page advertisement in the football program of the Hillsborough High School Terriers. A handgun was pictured at the top of the ad, over which was the name of Pidgeon's store. Discount coupons were displayed, including ''Lay-A-Way Available.'' A handgun that retailed for $79.95 was on sale for $44.50. A .22 automatic, usually for $89.95, was available for $54.50. A .38 revolver, retailing for $235.95, was now $160. Ankle holsters were marked down to $18.95. An ''ammo sale special'' offered 25 percent off. At the bottom, Pidgeon said, ''Good Luck Terriers!''

When some parents gagged on the placing of a gun ad in a high school program -- it is illegal to sell firearms to anyone under 21 -- Pidgeon found himself in a cross fire of controversy. The St. Petersburg Times reported the dispute.

In his store the other afternoon, Pidgeon said that the controversy is ''unwarranted. Definitely. Students go hunting. Students shoot in the Olympics. Why not advertise to them to let them know the availability of the products they want?''

Those who are alarmed about firearm deaths among children -- 1,000 youths are killed each year, 3,000 commit suicide with guns, and 400 die from gun accidents -- have an easy target in someone like Pidgeon. But he's the least of the problem. In this instance, he was responding as a generous businessman to an ad solicitation by the Hillsborough High football coach, who was raising money for the team. The Times quoted the coach: ''What's wrong with guns? There's nothing at all wrong with having a gun ad in a high school football program.''

At first, that sounds as monstrous as Pidgeon's statement about advertising to kids. Except their actions are legal. The law in Florida, recently loosened to make the state as much a shooting gallery as other states with lenient gun controls, now allows almost anyone to carry a concealed weapon. The Tampa Tribune, which had consistently editorialized against passage of the new legislation, calls Florida's new gun law ''terrifying'' and ''a demonic absurdity.''

The absurdists are found in the legislatures. Politicians who sit through hearings and hear from families of murder victims know the carnage statistics. They have been presented with evidence that it is 12 times more likely for a household gun to be used in the death of a family member or a friend than in that of an intruder. They have read the 1986 Gallup poll that shows a population favoring stricter handgun controls. They know that firearm death rates are lower where the laws are stricter and higher where the laws are looser. They have heard the surgeon general's 1981 Select Panel for the Promotion of Child Health call for ''a total ban on the sale of handguns.''

Still, many legislatures -- Florida's being the latest and grossest example -- pass laws of such leniency that a new gun is manufactured every 13 seconds. They embolden a football coach to ask, ''What's wrong with guns?'' and allow a gun dealer to present himself as a jolly good fellow molding future Olympians.

The same week that the Terriers of Tampa were being told of discounted revolvers and ankle holsters, Rep. George Miller (D-Calif.), chairman of the House Select Committee on Children, Youth and Families, was releasing ''Kids & Guns: A Child Safety Scandal.'' The report, published by the National Coalition to Ban Handguns and the American Youth Work Center, cited the latest figures of violence, ranging from nearly one child a week under age five killed unintentionally by firearms to the 4,400 youths who are gunned or who gun themselves to death.

William Treanor of the American Youth Work Center, a Washington group, believes that ''while some arguments can be made in favor of some type of gun ownership, none can be made that the flood of 150 million virtually unregulated guns is good for children.''

In Florida, the flooding has yet to crest. More deaths, more injuries, more family tragedies and more reports are apparently needed before the legislature says enough. Either that or new toy stores are needed -- Guns R Us.