The Anti-Tank Projectile That Turns Tanks to Liquid

Photo Credit: DoD / Getty Images
Photo Credit: DoD / Getty Images

The sabot round is a type of tank ammunition specifically engineered for armored warfare. This non-explosive anti-tank projectile is designed to strike targets with high precision, effectively disabling enemy units. Its deadly accuracy leaves little possibility of survival upon impact, making it a preferred option in military engagements.

Inner workings of the Sabot round

120 mm M829A2 round on display
120 mm M829A2 round. (Photo Credit: US Army / Wikimedia Commons / Public Domain)

The sabot round is engineered to house a sub-caliber projectile within the barrel, optimizing its exposure to propellant gases and increasing its muzzle velocity. This design ensures effective propulsion, even when encountering aerodynamic challenges.

As the round is fired, the sabot keeps the projectile stable throughout its flight and separates cleanly as it leaves the muzzle. The projectile, typically a slender rod of depleted uranium, reaches speeds of approximately 3,500 MPH, making it super effective at penetrating armor.

On impact, the projectile shatters, causing a destructive effect that soldiers often describe as turning everything inside enemy tanks or armored vehicles, including their occupants, into liquid.

The cup and expanding cup sabot rounds

Diagram showing the workings of the 125 mm BM15 armor-piercing fin-stabilized discarding sabot (APFSDS) round
125 mm BM15 armor-piercing fin-stabilized discarding sabot (APFSDS) round. (Photo Credit: US Navy / Wikimedia Commons / Public Domain)

There are five different types of sabot rounds. The cup sabot supports the base of the projectile and offers structural support around the shaft. It’s typically used in small arms ammunition, as well as smoothbore shotgun and muzzleloader projectiles.

The expanding cup sabot is similar to the cup round, in that it’s used for rifled small arms. However, when fired, the centrifugal force from the rotation of the projectile causes the segments surrounding it to open up. This introduces more surface area to the surrounding air pressure, releasing it.

Other types of sabot rounds

Diagram of the base sabot.
Diagram showing how the base sabot works. (Photo. Credits: Benchill / Wikimedia Commons CC BY-SA 3.0).

The base sabot has a one-piece base that supports the bottom of the projectile, as well as separate pieces that surround the sides and center, breaking away once the round has been fired. This sabot is considered superior to the previous two, as it offers a cleaner and better sabot-projectile separation. However, it’s more expensive to produce.

The spindle sabot is typically used in large caliber armor-piercing ammunition. It uses between two and four longitudinal rings with a center section that makes contact with the projectile. The front centers the projectile in the barrel and provides an air scoop to help with its separation from the sabot, while the rear seals the propellant gases with an obturator ring along the outside diameter.

Finally, the ring sabot uses the projectile’s rear fins to center it, forming a single ring around the front with an obturator ring to seal the gases. This type of sabot was favored by the Soviet Union, as the steel from which it was constructed could withstand launch accelerations without needing a ramp to support the projectiles.

Multiple generations of sabot round munitions

Sgt. Devon Myers carrying a sabot round
Sgt. Devon Myers, a tank commander with Company C, 1st Battalion, 64th Armor Regiment, carries a 120 mm sabot round to his tank for engagements at Fort Stewart-Hunter Army Airfield, Georgia, 2016. (Photo Credit: Spc. Ryan Tatum / Wikimedia Commons / Public Domain)

The M829A1, known as the “Silver Bullet,” is an armor-piercing fin-stabilized discarding sabot (APFSDS) round. It has a long-rod, uranium-depleted projectile that’s about 1.25 inches wide. Once it hits its target, it punches through armor and typically explodes an enemy tank in what tankers call a “jack in the box” effect.

According to Sofrep, the M829A1 “is widely regarded as the most effective tank-fired (M1 Abrams 120mm main gun) anti-armor weapons in the world. It overwhelmed Iraqi armor during Operation Desert Storm. The M829A1 is a depleted-uranium long-rod kinetic energy penetrator round capable of defeating heavily armored vehicles.”

Since then, multiple generations of the round have been developed. The M829A2 improved the structural quality of the uranium-depleted projectile, while the M829A3 made the propellant more efficient to boost muzzle velocity. The M829A4 uses a uranium-depleted projectile with a three-petal composite sabot.

Use during Operation Desert Storm

Tank firing a sabot round
A Sabot round goes down range at Marine Corps Air Ground Combat Center Twentynine Palms during Company A, 1st Tank Battalion’s annual gunnery qualification, 2013. (Photo Credit: Cpl. Sarah Dietz / U.S. Marine Corps / Wikimedia Commons / Public Domain).

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The M1A2 Abrams tank was used throughout Operation Desert Storm and fired 120 mm M829 sabot rounds at enemy armored vehicles; the projectiles took out multiple tanks as they dominated the battlefield. M829 sabot rounds are best used in armored warfare, rather than toward buildings or walls, so were thoroughly employed by the US military throughout the Gulf War.

Samantha Franco

Samantha Franco is a Freelance Content Writer who received her Bachelor of Arts degree in history from the University of Guelph, and her Master of Arts degree in history from the University of Western Ontario. Her research focused on Victorian, medical, and epidemiological history with a focus on childhood diseases. Stepping away from her academic career, Samantha previously worked as a Heritage Researcher and now writes content for multiple sites covering an array of historical topics.

In her spare time, Samantha enjoys reading, knitting, and hanging out with her dog, Chowder!

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