As of Tuesday afternoon, the post had been viewed more than 19 million times.
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In the video, Pappalardo, who has legally owned the gun for more than 30 years and sports a Second Amendment tattoo on his arm, talks about the need for new gun control laws.
After the school shooting in Sandy Hook, Connecticut, six years ago, Pappalardo said he would give up his gun if it saved even one child.
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"Since then more than 400 people have been shot in over 200 school shootings,” he said before destroying his weapon. “So I guess my words were just empty words in the spur of the moment. And now here we are, 17 more lives lost.”
He said he rejects common arguments that blame mental health issues or video games for such heinous crimes. “Ultimately, it’s a gun like this one.”
"I am going to give you a news flash. Until the other day, Nikolas Cruz was a legal gun owner. Steven Paddock in Las Vegas, killing 58 people, was a legal gun owner until that night,” he said. "For all you haters out there that think I'm very stupid for doing this, I hope and I pray that it doesn't take the barrel of one of these guns pointed at your child's head to change your mind.”
Pappalardo captioned his video, “My drop in a very large bucket #oneless.”
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He’s not the only gun owner to take a stand against rifles. On Friday, Ben Dickmann of Florida posted photos of himself handing his AR-15 variant over to law enforcement at the Broward County Sheriff’s office, the office working on the Marjory Stoneman Douglas High School shooting case.
"I could have easily sold this rifle, but no person needs this. I will be the change I want to see in this world. If our law makers will continue to close their eyes and open their wallets, I will lead by example," Dickmann wrote in his post.
Both Pappalardo and Dickmann were lauded for being examples of “heroes”, and many thanked them for their courage.
But not everyone agreed with their decisions. Some commenters called them “dumb” and “foolish” for giving up their guns.
On Tuesday, President Donald Trump said he has directed his attorney general to ban bump stocks, devices that make semi-automatic weapons capable of firing hundreds of rounds per minute.
According to CNN, when White House Press Secretary Sarah Sanders was asked on Tuesday whether Trump would support raising the federal age limit for military-style weapons, including the AR-15, Sanders said, "I think that's certainly something that's on the table for us to discuss and that we expect to come up over the next couple of weeks."
In most states, you must be 18 years old to purchase the AR-15. The age limit for handguns is 21.