Democratic lawmakers are eyeing a ban on .50-caliber sniper rifles (not all .50-caliber rifles are sniper rifles...what about those?) that can fire armor-piercing bullets and could cause catastrophic damage if used in attacks against airplanes and chemical-storage containers.

Rep. James P. Moran, Virginia Democrat, yesterday introduced a bill to ban the commercial sale of .50-caliber sniper rifles, with exemptions for military and law-enforcement use.

He said these weapons, which are less regulated than handguns, are accurate at 2,000 yards and can pierce the metal shells of rail cars carrying hazardous cargo and low-flying passenger aircraft.

He failed to note that many other rifles (and even some handguns) of smaller caliber will do the same thing.

"Just imagine if a terrorist got their hands on one of these guns and trained their sights on a train pulling hazardous cargo through the heart of Washington, D.C. It's a horrifying scenario that only a terrorist would want to see unfold," Mr. Moran said.

He said there is evidence that members of the al Qaeda terrorist group have purchased 25 of the weapons (horrors!). Mr. Moran said the weapons, which are sold legally to hunters and sportsmen for shooting competitions, should only be for military use.

A study conducted by the District-based Violence Policy Center (VPC) showed that rounds from a .50-caliber rifle can penetrate armor plating (so can a .223 Remington, often referred to as a "mouse-gun" caliber). In addition, explosive rounds for such weapons are available on the market.

"There is something gravely wrong with the virtually unregulated sale of these antiarmor guns in an era when our president tells us daily that we are in a war against terrorism," said Tom Diaz, VPC senior policy analyst, who urged Congress to pass Mr. Moran's bill.

But gun advocates said the bill is just another move to infringe upon the rights of law-abiding citizens to bear arms. "Since 9/11, gun-ban groups and politicians have shamelessly tried to tie their failing agenda for gun control to the terrorist attacks," said Andrew Arulanandam, spokesman for the National Rifle Association.

"The sad fact is that terrorists using box cutters, not guns, were the cause of those attacks."

The office of House Majority Leader Tom DeLay did not return calls for comment.

But the Texas Republican has torpedoed other Democratic efforts at gun control in the past, saying that there was no point in bringing to the floor this year a bill to extend the federal assault-weapons ban because "the votes aren't there."

The Senate has also proven a difficult place for gun restrictions, having defeated the assault-weapons extension over a provision to grant gun makers immunity from many civil lawsuits.

Only a few jurisdictions, such as Contra Costa County in California, have banned sales of the weapons. The New York state Assembly also has passed a bill to ban such sales, but the state Senate has yet to vote.