One gun owner in upstate New York sawed his AR-15 into three pieces in an online video that quickly went viral, asking, “Is the right to own this weapon more important than someone’s life?” In Broward County, Fla., another man asked the local sheriff’s office to destroy his AR-57 semiautomatic rifle.

But in interviews, other AR-15 owners said they swear by the guns. They called the rifle a lightweight, easy-to-fire symbol of their Second Amendment rights, and said they would never give up what they called a misunderstood weapon. In fact, one owners group, the AR-15 Gun Owners of America, said it had gained 10,000 new fans on its Facebook page since the shooting in Parkland.

Here are the perspectives from some of those AR-15 owners.

‘No Way an Assault Rifle’

Mr. Garcia said he bought his AR-15 about a year ago, and keeps it locked in a case inside his home in Rancho Cucamonga, in San Bernardino County, Calif. He said that he had a concealed-weapons permit, and that he went out with a handgun at all times.

“As we speak, I am armed,” he said.

He takes his AR-15 target-shooting, and like many other owners, said he liked to swap out the rifle’s components and after-market additions. At the shooting range, he said other gun owners often approached him and asked about how he had personalized the rifle to his liking.

Mr. Garcia, whose father served in the military, said he embraced the military roots of the AR-15. The Pentagon’s version of the rifle, renamed the M16 and capable of automatic or burst fire, was first distributed to American troops in Vietnam, and versions of the gun that do not fire automatically became enormously popular for civilian use. AR-15s were targeted under the Assault Weapons Ban from 1994 to 2004, but today are legal. Mr. Garcia said that his was made by Smith & Wesson, and that he had bought it for about $800.