US-Made .50-Caliber Ammo From Lake City Is Fueling Mexican Cartel Violence, Report Says

Mexican drug cartels have acquired .50-caliber ammunition produced for the US military and used those powerful rounds in firefights with police, to shoot down helicopters, assassinate officials and commit mass-casualty attacks, according to reporting based on New York Times investigations.

How Military Rounds Entered Criminal Hands

The rounds in question are manufactured at the Lake City Army Ammunition Plant, a US government-owned facility near Kansas City and the largest producer of rifle cartridges for the US military. Contracts and commercial agreements have allowed some military-grade ammunition to be sold into the civilian market, where it can be purchased and trafficked across the US–Mexico border.

Since 2012, US authorities have seized at least 40,370 rounds of .50-caliber ammunition in border states, and investigators say roughly one-third of those seizures are linked to Lake City-produced rounds. Cartels have also obtained .50-caliber ammunition from international suppliers in Brazil and South Korea.

Notable Incidents

Investigators cite several violent episodes that illustrate the damage these rounds can cause. In a 2019 attack in Villa Unión, Coahuila, more than 100 gunmen from the Cartel del Noreste opened sustained fire with heavy weapons and .50-caliber rifles, pinning down local police until the military intervened. Witnesses described the ground trembling under the fire; the clash left four police officers, two civilians and 19 cartel members dead.

The government-owned Lake City ammunition plant is the largest manufacturer of the US military’s rifle rounds - Justin Sullivan/Getty

At that crime scene, authorities recovered 45 .50-caliber casings stamped with the letters 'L.C.' — shorthand for Lake City. In a separate 2024 incident, attackers used Lake City-produced ammunition to penetrate the armor of an armoured police vehicle, killing one occupant and wounding three others. Mexico's then-defence secretary, Luis Cresencio Sandoval, warned that existing protective armour could not stop such rounds.

'The armour that we have cannot protect our personnel from this kind of penetration,' said Luis Cresencio Sandoval.

Trafficking Pathways And Commercial Sales

Investigators traced trafficking routes that include online retailers and at least one Texas gun shop. Authorities say a Texas dealer sold nearly 500 firearms that later reached cartel networks, including a .50-caliber machine gun and multiple .50-caliber rifles. At least 16 online vendors were identified as selling armour-piercing ammunition made at Lake City or assembled with components sourced from the facility.

One vendor, Vasily Campbell, told investigators he stopped selling the rounds about two years ago after becoming suspicious when buyers requested 100-round 'ammo cans' shipped to residential addresses.

A US Army spokesman said that selling commercial quantities from Lake City reduced government ammunition costs and saved taxpayers about $50 million per year. Critics and investigators argue those commercial sales, while financially beneficial, have created a diversion pathway that traffickers exploit.

What This Means

The presence of US-manufactured .50-caliber ammunition in cartel arsenals demonstrates how military-grade firepower can be diverted into criminal networks, dramatically escalating the lethality of confrontations with police and civilians. Investigators and officials are calling for closer controls and enforcement to prevent further trafficking while balancing procurement and budget considerations.