"Given the current climate with those products right now, we thought, 'Let's take a break for a year,' " Several said. "There's so much more to the show."
The decision came two months after the company announced that this year's expo would feature several tactical-firearms vendors for the first time.
By late Tuesday, a news release on the show's website was replaced with a statement explaining the organizer's change of heart.
As news leaked out earlier in the day, it angered gun-rights advocates.
"I'm outraged that the show would just roll over when it comes to the Second Amendment," read a comment on the show's Facebook page. "We will probably be seeking a refund."
Another comment: "Sellouts! Say goodbye to my family and money."
Many called for a boycott.
Since the announcement, from three to five exhibitors of the 1,200 scheduled for the expo have dropped out, Several said. Other vendors have urged the company to reconsider its ban.
"As a hunting-focused event, we welcome exhibitors who wish to showcase products and firearms that serve the traditional needs of the sport," Several said. "Clearly, we strongly support the Second Amendment."
Debate since the Newtown shootings has centered on AR-style rifles and high-volume magazines used by the shooter.
Gun-control advocates have called for state and federal bans, while firearms enthusiasts insist the weapons have lawful roles in sports such as hunting.
Even what to call the firearms has become a point of contention. Gun-control advocates use the term assault rifle, but groups such as the National Rifle Association maintain that such descriptions are inflammatory and encourage other terms, such as modern sporting rifles.
The uproar in Pennsylvania came as legislators in New York state were approving the toughest gun laws in the country, and one day before President Obama was set to unveil recommendations of a task force led by Vice President Biden and charged with examining ways to curb gun violence.
Shira Goodman, head of the gun-control group CeaseFirePA, hailed the show's decision as a welcome development in the debate.
"Banning those kinds of weapons at a gun show is a tacit acknowledgment that as a nation we will at least have a conversation about those guns," she said. It "shows that the exhibit organizer is trying to be a part of the solution."
Several resisted efforts to read too much into the decision.
"It's a very small, small part of the show," he said of the expo, which also features exhibitors peddling everything from camouflage clothing to camping supplies.
Several Pennsylvania firearms vendors scheduled to exhibit at the show did not return calls for comment.
Many were attending the National Shooting Hunting and Outdoor Trade Show, another Reed-run gun show expected to draw tens of thousands to Las Vegas over the next three days.
Steve Sanetti, chairman of the National Shooting Sports Foundation, welcomed manufacturers and shoppers to that event Tuesday with a speech in which he defended the industry.
"We are not the evildoers. You did not cause the monstrous crime in Newtown, and neither did we," he said. "Ours is a responsible industry that manufactures and sells lawful products to law-abiding citizens, who, in turn, exercise their constitutional right to own, use, and enjoy firearms safely and responsibly for lawful purposes."
Contact Jeremy Roebuck at 215-854-2620, firstname.lastname@example.org, or @jeremyrroebuck on Twitter.
Inquirer staff writer Amy Worden contributed to this article, which includes information from the Associated Press.