M - 29 Davy Crockett The M - 28 or M - 29 Davy Crockett Weapon System ( s ) Was the tactical nuclear recoilless gun for firing the M388 projectile nuclear That Was deployed by the United States During the Cold War . It was named after American soldier , congressman and folk hero , Davy Crockett ( 1786 – 1836 ) . Techinical Description . The Davy Crockett consisted of an XM - 388 Projectile Launched from Either the 120 - millimeter ( XM - 28 ) or 155 - millimeter ( XM - 29 ) recoilless rifle ( the 120 millimeter version is shown above ) . This weapon Had a maximum range of 1 : 24 miles ( 120 millimeter ) to 2 : 49 miles ( 155 millimeter ) . The XM - 388 casing ( including the warhead and fin assembly ) weighed 76 pounds , 30 inches long and Was Measured 11 inches in diameter ( at widest point ITS ) . The W54 warhead Used on the Davy Crockett weighed just 51 pounds and Was the smallest and lightest fission bomb ( implosion type ) ever deployed by the United States , with the variable kilotons explosive yield of 0 : 01 ( equivalent to 10 tons of TNT , or two to four times the powerful to the ammonium nitrate bomb Which destroyed the Alfred P . Murrah federal building in Oklahoma City on April 19 , 1995 ) , or 0 : 02 kilotons - 1 kiloton . A 58 . 6 pound variant . The B54 was Used in the Special Atomic Demolition Munition ( SADM ) , the nuclear land mine deployed in Europe , South Korea , Guam , and the United States from 1964 to 1989 . The Davy Crockett was deployed with U . S . Army forces from 1961 to 1971 . Between 1956 and 1963 , 2 , 100 were produced at an estimated cost ( excluding the warhead ) of the $ 540 million ( in constant 1996 dollars ) . The weapon ' s non - nuclear components were manufactured at the Rock Island Arsenal in Rock Island , Illinois . The W54 warhead was designed at the Los Alamos Scientific Laboratory ( now the Los Alamos National Laboratory ) and built by the Atomic Energy Commission . Stockpiled W54 warheads were test fired at the Nevada Test Site on July 7 and 17 , 1962 , during the " Little Feller II " and " Little Feller I " shots . In " Little Feller II " on July 7 , the warhead was suspended on cables about three feet above the ground ( yield was 22 tons ) . In " Little Feller I " on July 17 , a Davy Crockett was fired from a stationary 155 millimeter launcher ( in tandem with simulated battlefield maneuvers under Operation IVY FLATS ) and detonated about 20 feet above the ground at a distance of 9 , 357 feet ( 1 . 7 miles ) from the launch point ( yield was 18 tons ) . This test , the last atmospheric detonation at the Nevada Test Site , was observed by Attorney General Robert F . Kennedy and presidential adviser General Maxwell D . Taylor . Footage of Operation IVY FLATS was declassified by the Department of Energy on December 22 , 1997 . History . The Davy Crockett Atomic Battle Group Delivery System was born of a time where the US Army felt it needed some 151 , 000 nuclear weapons for deployment in a protracted conflict with the Soviet Union . Of this total , 106 , 000 would be for tactical battlefield use , 25 , 000 for air defense of US Army units and installations , and 20 , 000 to support his Allies . All of this was predicated on the thought at the US Army would use an estimated 423 atomic warheads in a single day of intense atomic combat - not to include surface - to - air missiles