The story of the M65 “Atomic Annie” cannon is an engaging portrait of the Cold War era—a time when nuclear war hung over everybody and military innovation was motivated by a desire for deterrence as much as for battlefield control. The Atomic Annie, a truck-mounted 280mm heavy gun, is an amazing indication of just how far the U.S. military would stretch in order to maintain its strategic edge.
Born from a mania of research and proliferation of atomic weapons, the M65 was the United States Army’s answer to the demand for mobile nuclear firepower. It was an homage to the large artillery cannons of World War II, namely the likes of Nazi Germany’s Krupp K5, infamously known as “Anzio Annie” for its strike against Allied forces in Italy. The legacy of the same can be identified in the M65’s similar function and designation.
Unveiling of the Atomic Annie was as much a demonstration of power as a practical military test. On May 25, 1953, at 8:31 am, within Operation UPSHOT-KNOTHOLE, the cannon fired a nuclear shell and produced a 15-kiloton explosion, equivalent to the Hiroshima bomb. One successful firing would establish the cannon’s place in military history, although it never saw deployment in the field.
The enormous size of the M65, around 85 tons, required two specifically made transporter trailers to transport it. The entire system, when equipped with the 280mm gun, was an imposing sight, 85 feet in length and over 86 tons heavy.
Now financed for the project at $800,000 per M65 unit, they waited to be sent out to U.S. bases across the world to serve as a warning to countries such as the USSR and North Korea. But once in operation, the M65 was rendered obsolete. More sophisticated nuclear delivery platforms in the shape of the B-52 Stratofortress bomber and the MGR-1 Honest John rocket made it apparent that a shell-type nuclear delivery system was not America’s future nuclear weapon.
The massive cannon, which could carry a nuclear warhead in the form of an artillery round, was soon replaced by more advanced delivery vehicles, such as the B-52 Stratofortress bomber and surface-to-surface missiles like the MGR-1 Honest John. The M65’s service life, between 1953 and 1963, was quite short, with the majority being scrapped, and the rest preserved as museum pieces.
The M65 Atomic Cannon systems were finally delivered to West German, South Korean, and U.S.-occupied Pacific Island of Okinawa proving grounds. Earlier, one was originally delivered to the Nevada National Security Site, previously the Nevada Proving Grounds, approximately 65 miles (105 km) northwest of Las Vegas. It was there on May 25, 1953, as part of a series of nuclear tests known as Operation Upshot-Knothole that an assembled M65 Atomic Cannon was loaded with a W9 nuclear shell and fired toward a target about seven miles (11 km) away.
