M103

United States tank

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Last updated

June 30, 2026

Quick Summary

The M103 was a heavy tank developed by the United States for service in the Cold War. It was designed to counter Soviet heavy tanks, particularly the IS-3 and IS-4. The M103 was armed with a powerful 120mm gun, which was capable of engaging enemy tanks at long ranges. It also featured heavy armor protection, making it a formidable opponent on the battlefield.

The M103 tank entered service in 1957 and was primarily used by the U.S. Army and the U.S. Marine Corps. It saw limited combat use, but it played a significant role in the development of tank technology and doctrine during the Cold War. The M103 was eventually replaced by the M60 Patton tank in the early 1960s.1

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tank
Gun calibre
But the heavy M103 tank, armed with a 120-mm gun, was only built in small numbers in the early 1950s. As a result, virtually the only battle tanks the U.S. Army had were the M46, M47, and M48 medium tanks, all armed with 90-mm guns. After the mid-1950s…
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But the heavy M103 tank, armed with a 120-mm gun, was only built in small numbers in the early 1950s. As a result, virtually the only battle tanks the U.S. Army had were the M46, M47, and M48 medium tanks, all armed with 90-mm guns. After the mid-1950s…
Read More