Sales of handguns and rifles at the show are subject to state and federal mandates, organizers said.
"The rules aren't changing because it's a gun show, or you get an exemption … the rules still apply there," Baker said.
State laws include a 10-day waiting period, valid identification and a registration fee.
"It's not the kind of event where everybody's walking out the door with firearms," Hoban said.
In accordance with state law, Baker said, attendees cannot bring loaded weapons to the show. Unloaded handguns must be transported in an approved case. Rifles may be hand-carried or taken inside within cases.
Bob Templeton, owner of Crossroads, said the Costa Mesa show typically draws 10,000 to 14,000 attendees but that number could swell to 16,000 to 20,000 this weekend.
He expected 8,000 people at the recent Ontario gun show but 16,000 showed up, as did some protesters.
"People are concerned about all the discussions at the national level about gun control and so forth," he said.
He called the fairgrounds "a very local event," adding that it's staged about five times a year with about 80% of attendees living in Orange County.
Crossroads plans to feature 200 to 240 vendors and 13,000 product tables in Orange County. The company does about 60 gun shows a year, mostly in the Western United States.
More than 407,000 customers went to Crossroads gun shows last year, which is the most of any gun show in the United States, according to its website.
Despite increased security, however, some have expressed reservations.
Kevin Wilkes, an Eastside Costa Mesa resident and father of a 7-year-old daughter, said the event's proximity to Costa Mesa High School, Orange Coast College and area parks is too close for his liking. He alluded to recent gun show shootings and the Sandy Hook Elementary School mass shooting.
"You have kids and sports fields and TeWinkle Park," he said. "Especially with what has just occurred recently at a gun show and at Newtown, it makes you stop and think … we're literally playing with a loaded gun here."
He said he favors the 2nd Amendment but would like to see an assault weapon ban, among other restrictions. Like most parents, he said he wants a safer environment for his family.
"I don't want to take anything away from people who collect … I'm gathering most people are good, law-abiding citizens," Wilkes said. "It's just a few who mess it up for everybody else."