The owner of a Bellevue, Washington, gun shop is dealing with backlash and praise from all sides on what he calls a common-sense solution following the fatal school shooting in Parkland, Florida.

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Jason Cazes, owner of lowpriceguns.com, now won’t sell an AR-15 or any long gun to anyone under age 21 unless they have military training.

“I woke up and it hit me,” Cazes said. “This Florida thing happened and the guy was 19.”

Cazes says the call to ban AR-15s won’t work and infringes on his rights. But he says he now believes anyone under 21 without military training isn’t mature enough to own one. He thinks his solution could work with the heated nationwide gun control debate. Neither side appears willing to budge.

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“Why am I the guy to do it, to offer the solution?” Cazes said. “I've been in the business 15 years. I've been in both sides politically. I lived in Louisiana for 20 years.”

His decision has led to a social media firestorm. He's been getting strong pushback, but also praise from both sides. And that's exactly what brought gun owner Greg Meserve to Cazes' gun shop for the first time on Tuesday.

“I support anyone who starts getting attacked for making common sense issues the norm,” Meserve said.

If you're buying any type of gun anywhere in the country, you have to fill out a federal form. And then your background check goes through the FBI database.

In Washington state, you only have to fill out the state form if you're buying a handgun.

You don't have to fill out that form or do a state background check if you're buying any type of long gun like a shotgun or AR-15. That's part of what Cazes wants to change.

Cazes says given the support he’s gotten from both sides, he wants to push the idea forward. On Tuesday, he was lined up for multiple national interviews. And a Tacoma gun shop owner reached out to help.

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"He said 'I have three master's degrees and one is in criminal justice and I'll help you write the bill,'" Cazes said. "I said 'Thanks. Let's get on it.'"

Cazes stresses the idea is a compromise.

“Even if it helps 5 percent less people going crazy from people who aren't mature enough to handle these sort of weapons, then that's worth it,” he said. “But on the other side, I want my right to own this (AR-15) as an adult. That is my choice of what I want to defend myself and my family with.”