Lucio R. Borderland Beat republish in part from Motherboard and BB Archives
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In October, 2014 The ATF agency along with Mexico’s PGR agency dismantled two shops, both in Jalisco, one in Guadalajara, that was producing AR-15 rifles. The factories were part of an network that sold its product to organized crime groups. This was the first of its kind to be discovered in Mexico.
The shops manufactured the weapons for organized crime groups in Michoacán and the local cartel, Cartel Jalisco New Generation (CJNG). It is estimated the shops were only operating for a few months. The material was imported from the United States.
Below is an extract from an in-depth article of the same subject from Motherboard titled “The Cartel Gunsmiths”, use the link to read full article.
Written by Brian Anderson
It was usually evening when the three men arrived at the shop. They would roll up in a Volkswagen Beetle, and come to a halt at a nondescript, garage-sized warehouse in a strip of shops in a residential neighborhood in Guadalajara, in Southwestern Mexico’s Jalisco state. They would park the Bug, and proceed to drink on the curb. Eventually the men would go inside, entering through a street door. They always locked the door behind them.
This went on for at least two months in 2014, according to a neighbor of the shop, where the men seemed to work odd hours. They never drew much attention to themselves, so there was little reason to believe their shop, located at calle Isla Trapani 2691, was in fact a sophisticated illegal gun manufacturing plant, and that the three of them were using the space to quietly produce homemade, untraceable firearms for one of Mexico’s fastest-growing and violent crime syndicates.
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| lower receivers |
Inside the shop, the men mostly made AR-15s. These air-cooled, magazine-fed rifles have become ubiquitous among Mexican narcos; they’re relatively lightweight, and can take a beating. At their secret lab in Guadalajara, the three men fashioned the AR-15s from an assemblage of firearms components purchased in borderland gun shops in the US, and then smuggled into Mexico in small batches, according to officials from both countries who were interviewed for this story.
But as Mexican authorities discovered when they raided the shop, with support from American officials, on October 7, the men also milled functioning AR-15 lower receivers from unfinished blocks of aluminum. The lower receiver houses an AR-15's main firing mechanism, and by Mexican and American law is the only part of the rifle that's legally defined and controlled as the "firearm."* The men made these lowers in-house with the same sort of milling technology now embraced by a worldwide maker movement. In Mexico and the US, legal lower receivers bear serial numbers designed to make the firearms traceable. The homemade Jalisco cartel guns, being unserialized, are nearly impossible to track with a level of certainty.
Organized crime groups in Mexico have long trafficked in illegal firearms, but cartels need firepower now more than ever as they diversify their portfolios, adding oil theft, extortion, kidnapping, and human trafficking to the mix, along with drug running. Here, for the first time, was evidence of a cartel making its own firearms too. Was it just a one-off novelty, or an omen?
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They hid in plain sight, the homebrew gun club for a powerful new gang, the Jalisco New Generation Cartel. The Jalisco cartel has undergone such a meteoric, savage rise to power in the last few months that the head of criminal investigations for Mexico’s attorney general labeled the gang a “red flag.” The group is terrorizing the region with coordinated attacks on government installations. In May, Jalisco cartel members downed a Mexican military helicopter with a rocket-propelled grenade. Six soldiers were killed. The Jalisco cartel is also behind a rash of fiery roadblocks, in which cartel operatives set large vehicles and gas stations ablaze as a show of strength and to incite chaos. The cartel has been behind 39 of these roadblocks as of today; one of them, just blocks away from the site of the gang's boutique gun lab, involved a public transit bus.
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| finished lower receiver |
The lower receiver is the crux of an AR-15. It plays host to the rifle's trigger mechanism, and conjoins the stock, grip, and magazine, as well as the upper receiver, to which the barrel mounts. For a rifle like an AR-15 that has both upper and lower receivers, only the lower receiver is considered the firearm, making the rest of the gun's parts far easier to acquire and harder to trace.
The DIY gun machining process often begins with a "blank," an unfinished piece of material that, with the right tooling, can be augmented to house the actual firing mechanism. The US Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) doesn’t consider a blank to be in a “stage of manufacture," which is when the firearm must be classified per the US Gun Control Act, if it's 80 percent or less complete. In other words, the blanks widely known as "80 percent lowers"—meaning they have a solid fire control cavity not yet machined with holes or divots for a fire selector, firing pins, or a trigger—are not legally considered guns by the ATF, and can be purchased off the shelf in the US but not in Mexico.
It’s only once that cavity is properly machined to house a firing mechanism that the unfinished 80 percent lower receiver becomes a finished lower receiver, at which point it meets the legal definition of a “firearm” in both Mexico and the United States. It is then subject to government regulation, and must be issued and stamped with a serial number.
Amateur machinists and gunsmiths have been tooling functional lower receivers from 80 percent blanks for decades. Today, there are a few ways to do this for an untraceable AR-15: with a good, old-fashioned drill press, similar to the hand drill used in this ATF demo; with a 3D printer; and with a computer-numerical control (CNC) mill that can automatically machine an untraceable gun out of metal.
But the men weren’t merely finishing the job on receiver blanks at the lab in Guadalajara. They were creating new lowers altogether.
A finished lower receiver might be what makes a gun “a gun” in the eyes of the law on both sides of the Mexico-US border. But even a firearms novice knows there’s a lot more to a gun than that. Where did all the other gun parts—the stocks, grips, magazines, barrels, ammo, and so on—that funneled to the Jalisco cartel’s illegal arms factory come from?
Special Agent Keith Heinzerling, of the US ATF, said we don’t know because gun parts cannot be traced as they are recovered within Mexico. A serial number is required to conduct a trace via the ATF’s e-Trace system for tracking recovered firearms, and gun parts, with the exception of the receiver or frame, do not bear serial numbers per the GCA. They therefore cannot be traced.
“You could surmise that [the parts] are coming from the US, since most of the weapons that come down here illegally are from the US,” Heinzerling, the ATF country attaché to the US Embassy in Mexico City, told me over the phone. “But we don’t have our finger on that. There’s no way to trace them back.”