What should America do with its unwanted guns?
At steel mills around the country, the answer is simple: Throw them into a giant caldron, heat them up to 3,000 degrees Fahrenheit and liquefy them into an orange ooze.
For years, firearms at these so-called gun melts have served as an inexpensive supply of scrap metal that can be turned into bars of high-grade steel and later used as components in mining, construction and energy projects.
And as recent shootings have put gun control into the headlines, interest in gun melts is increasing at some mills.
More than a thousand guns were turned in last month in St. Paul at a steel mill run by Gerdau Long Steel North America, a subsidiary of a Brazilian company that processes scrap metal. The mill has produced steel used in wind turbine foundations, Harley-Davidson motorcycles and Caterpillar equipment.
The firearms come from a variety of sources: rifles confiscated by the police, shotguns surrendered by owners, handguns used as evidence in closed cases and deactivated service weapons.
A spate of mass shootings in the past year has led to boycotts, protests and legislation on both sides of the gun control debate. Using the hashtag #OneLess, some gun owners publicly pledged to destroy or give up their assault-style firearms. Dick’s Sporting Goods said it had stopped selling the high-powered guns and would destroy its remaining inventory.
Artists have forged garden tools and jewelry from old rifles and pistols. A line of watches made from firearms seized from conflict-torn regions has garnered some $400,000 in pledges on Kickstarter — well over 10 times the goal.
For years, police departments and community groups have held gun buyback events around the United States, trading cash, gift cards and grocery vouchers for firearms handed over to law enforcement. Many reported an upswing in participation this year.
Many more guns than in previous years are being run through the shredding machines at GunBusters, a Missouri-based chain that pulverizes firearms around the country and sells any salvaged parts to gunsmiths and gun dealers, executives said. The company also makes money by recycling the resulting scrap steel.
In other parts of the country, unwanted firearms are sent to gun melts at steel mills, including Gerdau’s.
The St. Paul facility conducts its semiannual melt for free in exchange for the steel the firearms provide. The guns contribute a tiny portion of the 400,000 tons of steel that the St. Paul plant produces each year, but free metal is hard to turn away when scrap is expensive.
County sheriff’s offices, small-town police departments and even airport law enforcement agencies participate.
Before each melt, a caravan of police cruisers, box trucks and trailers moves through radiation detectors — a standard precaution outside the St. Paul mill, which also processes a small amount of metal from the medical industry — before unloading their cargo.
The piles are usually studded with knives and, occasionally, some grenades, but the bulk consists of guns that have been stripped of ammunition.
A magnetic crane then hoists the firearms and plops them into a bucket that can hold 45 tons, which is driven into a warehouse. There, the bucket is positioned over a furnace, and at the right moment, its bottom opens like a clamshell.
The guns tumble into a pool of molten metal, causing a small fireball, said John Skelley, an environmental affairs manager for Gerdau Long Steel. The weapons, heated by arcs of electricity, dissolve inside the furnace.
“It’s like an ice cube in a drink on a hot summer day, except it’s 3,000 degrees Fahrenheit and it’s a piece of steel melting,” he said.
In a single hour, the main furnace uses the same amount of electricity that three or four houses require in an entire year. The gun tincture often spends an hour and 20 minutes inside the caldron.
It’s not a quiet process.
“While it’s melting and arcing and going, it’s quite vigorous, like the roar of a jet engine in an airport,” Mr. Skelley said. “As the steel gets melted, it calms down a lot, and it’s a loud hum like a lawn tractor.”
Eventually, the liquefied guns are poured into a ladle and sent to a refining station at the plant, and then on to a separate machine to be solidified. Gerdau installed the machine, an integral part of the mill’s operations known as a caster, for $60 million in 2014 with incentives and support from the Minnesota Chamber of Commerce and state and local governments.
The caster is so large that it sits in its own eight-story warehouse, forming the molten steel into long rectangular blocks called billets and then cooling them. Later, Gerdau will move the billets into a furnace where they will be heated to more than 2,000 degrees and softened so they can be rerolled, “like Play-Doh,” into products, Mr. Skelley said.
Distributors then sell the steel to a variety of industrial customers. Steel from Gerdau facilities has been used in the 1 World Trade Center tower, the Burj Khalifa tower in the United Arab Emirates and the Taipei 101 tower in Taiwan.
Could distributors sell to gun makers?
“Absolutely,” Mr. Skelley said. “That’s something we have no control over.”