Some people showed up as early as 2 a.m. to line up at the Orange County Fair Grounds for the Crossroads of the West Show.
The increased interest is being attributed to the possibility of new federal regulations that could make it more difficult to buy guns and ammunition. Some gun show attendees say the possibility of stricter laws has created what they call "panic buying."
Gun show organizers say nothing boosts business like talk of a ban.
The federal government has had several discussions on stricter gun laws after the mass shooting in Newtown, Conn.
One item being considered is limiting the number of bullets in magazines to 10 rounds. More comprehensive background checks are also being considered, including closing the so-called "gun show loophole," where people can attend a show and buy a gun without a background check.
People at the gun show say they're passionate about protecting their Second Amendment rights, and some believe a common ground can be found between those for and against stricter laws.
"California currently has, as far as I'm concerned, the most strictest gun laws in the nation. You can't have high-capacity magazines, you currently can't have assault weapons, and we require a 10-day background check - it doesn't matter whether it's a rifle or a handgun. Apply that to the rest of the nation," said Andrew Cowie of Santa Ana.
Donald Pinkus from Rancho Cucamonga said he came to the gun show to protect his Second Amendment rights.
"This country is defended by our Second Amendment right, and we're here supporting that. We're here believing in that," Pinkus said. "Some people may think, you know, those crazy gun people and all that, but you know what, we're just average people here. We're just here to protect ourselves and our families and keep our country free. That's the way it is."
Meantime, a gun control rally took place Saturday morning at the National Mall in Washington, D.C. Thousands, including Newtown residents, were expected to participate. March organizers support President Barack Obama's call for a ban on military-style assault weapons and high-capacity magazines and universal background checks for gun sales. They also want lawmakers to require gun safety training for all buyers of firearms.