Shot gunning from a tank: M1028

Steve Johnson
by Steve Johnson

The M1028 is a 120mm shotgun shell for the M1 tank. The shell holds 1100 10mm tungsten balls. They are apparently lethal up to 700m (765 yards). Here is a video of the shell being fired in slow motion. It shows the shot breaking the sound barrier and the shot pattern (H/T to Sebastian).

I tried to calculate the weight of each ball. It depends on how pure the balls are. My calculations, based on a company that makes tungsten balls that weigh 18 grams per cm3, indicate that each ball will weigh about 145 grains. That is a combined weight of 159,500 grains / 10 kilograms / 22.8 pounds!

(4/3) x pie x 0.5cm ^ 3 = 0.52 cm3
0.52 * 18 = 9.42 grams (145 grains)

Please correct me if I am wrong.

The requirements of the round were:

  • Defeat >50% Advancing Squad w/ 1 Shot
  • Defeat >50% Advancing Platoon w/ 2 Shots
  • 200-500M (threshold)/100-700M (objective)
  • Muzzle Action (i.e. No Fuze)
  • No orientation of the projectile
  • Vulnerability no worse than current fielded

The M1028 cross section.

Here is a before and after shot taking during the testing of the round. I am not sure of the range.


Two dummies survived, the wall did not.

The concept of shot is not new. Grape shot or loose stones, metal and glass have been used for as long as cannons have.

American Revolution grapeshot

Sources of information:

M1028 – GARM Final (PDF)
JinJu Powder Metallurgy

Steve Johnson
Steve Johnson

I founded TFB in 2007 and over 10 years worked tirelessly, with the help of my team, to build it up into the largest gun blog online. I retired as Editor in Chief in 2017. During my decade at TFB I was fortunate to work with the most amazing talented writers and genuinely good people!

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2 of 24 comments
  • Zera Zera on Dec 03, 2012

    As crude as it is to say, I'm inclined to admit that I call this kind of round "120mm CC." 'Closed Casket.'

  • Sam Suggs Sam Suggs on Feb 10, 2013

    this concept is ancient. two dummies survived is probly a bit pursumtuiouse