WASHINGTON - With President Obama's gun-control agenda in jeopardy, Vice President Joe Biden today said it is "mind-boggling" that lawmakers would try to block debate on a gun bill and delivered an emotional call to action.

Just hours after meeting privately with families of the victims of the Newtown, Conn., massacre, Biden said lawmakers threatening to filibuster gun legislation have lost sight of the pain of these parents.

"Why don't people up there understand this? I mean, what has to happen to break through the consciousness of the people up on the Hill?" he asked.

Speaking to law enforcement officials at the White House, Biden said he wished members of Congress had been able to "eavesdrop" on his discussion with the parents of children at the Sandy Hook Elementary School, where 20 children and six adults were killed in a shooting in December.

"[The families] don't understand how we could even be at this point debating this," he said. "The truth is, they don't see how 100 bright women and men don't get it."

More than a dozen Republicans are threatening to block a vote on the bill.

"Not only are some of the senators not willing to stand and be counted, they're prepared to stop anybody from being able to be counted. I mean, it's almost mind-boggling," Biden said.

"You've got leading senators, the most august body in the world, legislative body in the world - they're saying we're not even going to talk about this, a tragedy that traumatized the nation and caught the attention of the entire world," he said. "And after all the thinking and the debate and the discussion with overwhelming majority of the American people thinking that the proposals the president put forward make absolute sense, the climax of this tragedy could be we're not even going to get a vote?

"I can't believe it. I mean, at the end of the day I can't believe that it will actually happen," he said.

The vice president accused the National Rifle Association of engaging in a campaign of "disinformation" about the administration's proposals in an effort to try and scare people.

"Kind of scary, man. Black helicopter crowd really is upset," he said.

Biden insisted there would be no central registry and no way for the government to keep records on gun owners.

"No way that Uncle Sam can go find out whether you own a gun because we're about to really take away all your rights and you're not going to be able to defend yourself and we're going to swoop down with Special Forces, folks, and gather up every gun in America," he said. "It's bizarre, but that's what's being sold out there."

The vice president concluded his remarks with an urgent appeal to his opponents.

"What are you going to say to those parents? Look them in the eye and tell them you concluded there's nothing you can do?" he said. "We have an obligation to try. We know if we do the things we're talking about, we will save lives."