Some two dozen deaths and hundreds of injuries have been linked to accidental firings of the guns. The 2010 documentary Remington Under Fire: A CNBC Investigation explored allegations that for more than 60 years, the company covered up the alleged defect.
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Remington has steadfastly denied the allegations and still maintains the guns are safe.
"There's nothing wrong with the Remington 700 rifle," said Remington outside counsel John Sherk at a preliminary hearing in a federal court in Kansas City to consider the proposed settlement. But he said "Remington is committed to this settlement" in order for the company to move past litigation that has gone on for decades.
The proposed settlement involves Remington rifle models 700, Seven, Sportsman 78, 673, 710, 715, 770, 600, 660, XP-100, 721, 722 and 725. All contain a tiny internal part known as a "trigger connector" which critics say can cause the guns to malfunction.
Attorneys for the plaintiffs also argued that the deal is fair, even though in a limited number of cases involving guns they say are too old to be retrofitted, customers will merely receive vouchers worth $10 or $12.50 worth of Remington products.
U.S. District Judge Ortrie Smith wanted to know if the parties had considered offering to buy back the guns instead.
"If the guns are defective, why are they still out there?" Smith asked.
At issue are some 600,000 guns including the Model 600, which has a similar firing mechanism to the 700 series but was recalled and discontinued in the 1970s. Plaintiffs' attorney Jon Robinson said most of the guns in question are so old, they are "probably in a closet somewhere." If not, and they have not caused a problem by now, he said, they are "probably not a problem." Besides he said, the proposed settlement does not prevent gun owners from filing personal injury claims later should a gun malfunction.
But the judge was skeptical.
"The problem with your approach, Mr. Robinson, is that first, somebody's got to get hurt," he said.
Echoing that concern is Richard Barber of Montana, whose 9-year-old son was killed in 2000 when a Remington 700 rifle accidentally fired during a family hunting trip. Barber, who has compiled millions of Remington documents and settled a lawsuit of his own against the company, has been a driving force in the push to change the trigger. He did not attend the hearing but spoke to CNBC by phone.
"I don't know whether I'm going to object to the settlement per se," Barber said. "But I am going to send a letter to the judge, complete with documents."
Barber notes that Remington manufactured the older guns in question while it was owned by E.I. duPont de Nemours, which is also a party in the settlement. DuPont sold Remington in 1993 but is generally responsible for liability in products discontinued before then.
Meantime, it was revealed on the eve of the hearing that a key consultant for the plaintiffs, firearms expert H. Jack Belk, was quitting the case and planned to formally object to the settlement. Belk, who has testified against Remington as a paid expert in dozens of cases and appeared in the CNBC documentary, said he had concerns about the trigger Remington was offering as a replacement, known as the XMark Pro.
While Belk told CNBC the new trigger is a superior design, the manufacturing process could make it vulnerable to wearing out prematurely.
"What I'm seeing in the field is that we're trying to replace a defect in design with a defect in material," he said in an interview.
Both Remington and the plaintiffs say they have thoroughly reviewed the XMark Pro manufacturing process and Belk's concerns are unfounded. Besides, they said in court filings, Belk is not an expert on metals or manufacturing.
Read MoreJudge questions Remington rifle settlement
Judge Smith said he would take up Belk's concerns later in the process.
Since the parties began moving toward a settlement last year, Smith has raised repeated questions. Last fall, he denied a request by both sides to keep key evidence and documents in the case under wraps, saying it was in the public's interest to keep the material accessible. Then, after the tentative settlement was filed Dec. 5, he demanded to know why owners of certain models were being treated differently than others, whether a $12.50 product voucher was adequate compensation for a gun that might still malfunction. And he questioned whether Remington would publicize the settlement aggressively enough. He also questioned a provision that would allow the company to back out of the deal if too many customers opt out in order to pursue claims of their own.
At Wednesday's hearing, attorneys for both sides defended the voucher arrangement.
"People don't want to give up their guns," Sherk said. Besides, he said, there are more than 300 products on sale at Remington's website for under $10, including gun-cleaning supplies and a silicone "gun sock," so the vouchers have "real value."
Sherk said Remington would "prominently" feature a link to settlement information on its website.
As for the opt-out provisions, attorneys said they were concerned that other plaintiffs might try to extract more from Remington by filing competing lawsuits instead of joining the settlement. The judge agreed to hear arguments about the issue behind closed doors.
Smith said he would issue a preliminary opinion on the proposed settlement soon, and that a hearing on final approval of the settlement, complete with evidence and sworn testimony, would likely occur this year.
None of the attorneys would comment following the hearing. In a joint statement this afternoon, the two sides said they would not have anything more to say until the judge rules.
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Remington's owner, Cerberus Capital Management, has been seeking to exit the gun business since the 2012 school shootings at Sandy Hook Elementary School in Connecticut. The company has been unable to find a buyer.