A report released Thursday highlighted that more than 16,000 firearms have been reported "lost" from licensed gun manufacturing plants before sale since 2009, an average of 18 guns lost per day. Many of these guns don't have serial numbers affixed yet, making them nearly impossible to trace and thus desirable for criminals.

The Brady Center to Prevent Gun Violence's report, "Missing Guns: Lost and Dangerous" (PDF), used data gathered by the Bureau of Alcohol, Tobacco and Firearms and makes an argument for amendments to federal laws governing gun manufacturers.

Daniel Vice, the center's senior attorney and the author of the report, told Raw Story that the lack of security and hiring standards at the plants contributes to the gun losses.

"Federal law is so weak that there's no law that says they have to do anything to secure their plants," Vice said. "They can write off 'lost' guns as a business expense. They can leave their doors wide open at night if they want to."

Some gun manufacturers, such as Massachusetts-based Kahr Arms, hire drug addicts and others who are likely to have unsavory connections and federal law does not require background checks when entrusting employees with the unstamped guns. The Brady Center's Legal Action Project, representing the family of a man who was killed with one of Kahr's unstamped "lost" guns, won a $600,000 settlement against Kahr for the family in July, the largest damages payment ever against a gun manufacturer charged with negligence.

When a gun is "lost," Vice said, it is usually because it has been stolen or sold illegally to avoid a background check and record of ownership. A 2004 law referred to as the Tiahrt Amendment blocks manufacturers from having to take inventory and account for their guns annually, a victory for the pro-gun lobby. The amendment also adds a veil of secrecy, blocking the press and public from finding out how many guns were lost from each manufacturer, though the information is reported to the ATF.

"When manufacturers are making a product as deadly as guns, we shouldn't allow them to decide that this is a business expense they can write off when their guns leave their plant and end up in the hands of criminals," Vice said.

President Barack Obama campaigned on repealing the Tiahrt Amendment, but has instead attached the law's renewal to annual budget proposals, keeping the law in use.

The recent scandal involving the ATF's loss of a huge amount of arms to traffickers in Mexico in the "Fast and Furious" operation highlights the firearms industry's lack of accountability, Vice said.

"Our gun laws are so weak that gun dealers and manufacturers can just let guns leave their facilities without background checks," he said. "What that frequently means is off-the-book gun sales. Or dealers can just claim it was stolen and many dealers have had hundreds of guns missing from their inventory — which frequently means they've engaged in large-scale arms trafficking."

The report will be used by the Brady Campaign to lobby for stricter gun laws. It isn't in the interest of safety to allow the lack of security and accountability to continue, Vice said.

"This is something completely in the control of gun manufacturers," he said. "This is their own inventory and yet they allow thousands of guns to leave their inventory without background checks or records of sale, rather than take simple steps to control their own guns and their own facilities."