After the first primitive tanks arrived on the battlefields of Western Europe in the Great War, the U.S. Army and Marines kept an eye out for something more portable and compact than a field gun to poke holes in those “land dreadnoughts.” While Dr. Robert H. Goddard, grandfather of American rocketry, was working on a man-portable anti-tank device in 1918, peace broke out and his research stopped.
This meant that the closest answer the interwar military came up with to zap panzers was the M3 37mm anti-tank gun. While over 23,000 of these were made, they were still bulky, at 912-pounds, and could only penetrate 2.1-inches of plate at 1,000 yards, which was fine for 1930s tanks but didn’t cut the mustard with more significant armored vehicles.
Developments in small arms by early 1942 led to the M9 rifle grenade, a 1.2-pound bottle rocket that could be fired from the M1 Garand or M1903 Springfield and its 4-ounce hollow charge could make a splash against pillboxes but, like the 37mm gun, proved less impressive against better tanks.
The next step up was the 12-pound 2.36-inch (60mm) Rocket Launcher, M1, which went down in the books as the first “bazooka” in late 1942.
Unpopular due to their notoriously bum rockets, the device was upgraded to the M1A1 and finally to the M9 bazooka, with the latter weighing 17.8-pounds when ready to fire its slightly better M6A3 rocket. About the best American man-portable anti-tank weapon of WWII, capable of penetrating about 4-inches of armor, it was still ineffective against medium or heavy tanks of the day such as the Panther and Tiger.
Meanwhile, the 88mm German RPzB 54 Panzerschreck, designed to knock out Soviet beasts en mass, was a much better device. Dubbed the ofenrohr (stovepipe) by the Landsers that used it, the RPzB 54 could slice through as much as 9-inches of armor.
Nonetheless, when Task Force Smith got wheels up from Japan to Korea in July 1950 to stop the onslaught of North Korean aggression over their less well-equipped neighbor to the south of the 38th Parallel, the Joes still carried the M9A1 into battle. When pitted against Soviet-supplied T-34-85 tanks at Daejeon, vehicles which had nearly 4-inches of armor in spots, those 60mm spitball shooters were wishful thinking.
Luckily at the time, at Rock Island Arsenal, a supply of the brand new and very Panzerschreck-like 90mm 3.5-inch M20A1B1 rocket launcher, dubbed the “Superbazooka,” were on hand. Loaded on aircraft in Illinois on 12 July 1950, they were sped directly to the warzone.
As noted by the RIA Museum, this “marked the first time equipment was shipped from the Arsenal, directly to troops in the field utilizing air transport.”
Just six days after the emergency batch of Superbazookas left RIA, they were used in combat by elements of the 24th Infantry Division who knocked out eight T-34s on 18 July– 70 years ago today. Capable of penetrating up to 11-inches of armor, the Joes went from being hunted by tanks to being tank hunters, a tactic the winding and hilly Korean countryside favored.
The Superbazooka, coupled with more powerful follow-on U.S. MBTs like the M26 Pershing and M46 Patton tanks and effective close-in air-support, effectively ended the reign of the T-34-85 in Korea.
By the time the North Koreans were forced to withdraw from the south in September, some 239 T-34s and 74 SU-76 assault guns had been lost or abandoned. After October 1950, tanks became scarce in the DPRK Army and remained that way for the rest of the war.
The Army and Marines kept the M20 around through the 1960s until it was replaced by the even more compact M72 66mm rocket. It hung out in National Guard armories even longer.
The M20 was used overseas extensively, with some being collected in the 1990s by NATO forces in the former Yugoslavia. A Spanish-made clone, the 88.9mm Instalaza M65, updated with an improved ignition method and new ammunition types, saw action in the Falklands and remaining in service with the Spaniards until just recently. They are a hit on the surplus market, and I just happen to have one of my own, in well-used condition.