Biden, doing a Google+ “hangout” to promote President Barack Obama’s proposals for battling gun violence, had been asked whether a new assault weapons ban might infringe on the Second Amendment rights of those who want one “as a last line of defense” to fend off looters after “some terrible natural disaster.”

“Guess what? A shotgun will keep you a lot safer, a double-barreled shotgun, than the assault weapon in somebody’s hands [who] doesn’t know how to use it, even one who does know how to use it,” the outspoken vice president, a shotgun owner himself, replied. “It’s harder to use an assault weapon to hit something than it is a shotgun. You want to keep people away in an earthquake? Buy some shotgun shells.”

With the fate of Obama’s gun violence proposals unclear in the face of stiff opposition from most Republicans and some Democrats, Biden urged supporters of ideas like imposing a new assault weapons ban, limiting ammunition clips to 10 rounds and toughening background checks to pressure their elected representatives. “This town listens when people rise up and speak,” Biden said.

Like Obama before him, the vice president emphasized that he's a firm believer in the Second Amendment—but compared proposed new curbs on assault weapons to keeping fully-equipped F-15 fighter jets off the market.

“You have an individual right to own a weapon both for recreation, for hunting and also for your self-protection,” he said. "But just as you don’t have an individual right to go out and buy an F-15—if you’re a billionaire—with ordnance on it, just like you don’t have the right to buy an M-1 tank, just like you don’t have a right to buy an automatic weapon" you should not be able to get other weapons for which there is "no reasonable societal justification, or constitutional justification."

Biden noted that "it's not about keeping bad guns out of the hands of good people, it's about keeping all guns out of the hands of bad people. There should be rational limits."

One of Biden's questioners asked why, if they're rational, there's the lack of political will to enact them.

Biden paused, then said he would have to watch his words. “Both left and right sometimes take absolutist positions," he said.

The vice president emphasized that the administration was not calling for armed guards in schools, a proposal recently floated by the National Rifle Association. Instead, schools would have the flexibility to hire a uniformed guard, armed or not, if they so desired.

But Biden warned it would be a "terrible mistake" to arm school staff. "The last thing we need to do is be arming schoolteachers and administrators" who may not have firearm training, he said.