M20A1B1 Super Bazooka – It’s a Super Bazooka. Need I Say More?

The US was one of the few major military powers that went into World War II without a substantial infantry antitank weapon. Most countries had an antitank rifle of some sort, but the US just had some marginal antitank rifle grenades. That was rectified in late 1942 when the M1 Rocket Launcher – aka the Bazooka – was introduced. Using a 2.36” shaped charge warhead, it was able to penetrate about 4.7 inches of armor, which was effective through most of the war. A larger version went into development in 1943 though, because it was clear that the M1 would soon become obsolete.

The 3.5” M20 Super Bazooka was adopted in late 1945 and put into production in 1948, with it s first combat use coming in the Korean War. It was much more powerful, capable of penetrating 11 inches of armor plate. The launchers itself weighed just 13 pounds, with each rocket adding another 8.9 pounds. This, and the updated M20A1, would serve as the main US infantry antitank weapon until replaced by the 90mm recoilless rifle in the 1960s.

46 Comments

  1. “Most countries had an antitank rifle of some sort, but the US just had some marginal antitank rifle grenades.”
    There was AT rifle developed in United Stated during World War II, but it was not produced as by time it was ready, penetration become too small due to progress in thickness of armor of tanks. See: http://weaponsman.com/?p=29717

  2. From Wikipedia, there was a popular radio comedian of the day named Bob Burns who had a musical instrument he called a “bazooka.” During the testing process, someone observed that the weapon resembled the musical instrument.
    One of your most interesting presentations. Thanks.

      • There probably are no original rocket projectiles in firing condition left anywhere. Solid fuel rocket motors have a shelf life of about 20 years, after which the burn rate becomes unpredictable. I don’t know, but I suspect production of rockets for the M20 ended decades ago.

        You probably could manufacture a practice projectile with an inert warhead, but unless you knew and replicated the original formula of the propellant exactly, firing the thing from shoulder would be dangerous. Radio controlled remote firing would be the way to go. There are companies which make solid fuel rockets for amateur rocketry (it requires a license in the US and in the EU), but still it would be major project to make functioning rocket.

        • As recently as a decade ago, Norinco still marketed new-manufactured rounds for the M20 ATRL (Anti-Tank Rocket Launcher), due to the significant numbers held in inventory by Second and Third World armies, notably South American ones that received them under MAP in the 1960s and 1970s, when they were retired from the active U.S. inventory with the introduction of the M72 LAWS.

          Most demand was for the straight HEAT (High Explosive Anti-Tank, i.e. shaped-charge) round, but they also made a “smoke” round with a white phosphorus (WP) warhead.

          Of course, officially, use of “Willy Pete” against enemy personnel is prohibited by the Hague Convention. but there seemed to be a good amount of market for those “smoke” rounds, just as there is to this day for WP rounds for mortars from 60mm on up to 107mm.

          cheers

          eon

          • WP is not that effective in the open, in other words its usually less effective than napalm or conventional fragmentation munitions, but it’s very good at setting forest or any structures with anything burning on fire. It can also be used against bunkers and tunnels to consume all the oxygen and asphyxiate occupants. These uses against military targets are NOT prohibited by any treaties. Only use as a chemical agent is prohibited, but in most cases the direct chemical effect of WP is secondary to the burning (either direct or indirect) and asphyxiation effects, so usually WP is not considered a prohibited weapon against military targets. It is, however, prohibited to use any incendiary weapons against civilian targets.

          • Two things:
            First the acronym is LAW. It’s only called a “LAWS” in the world of Dirty Harry movies.

            Second, unless you have a specific reference in the Hague Convention there’s no prohibition against using WP on enemy personnel. It’s prohibited against civilians and being used when military targets are in close proximity to civilians but that whole “WP can’t be used against enemy personnel but it’s a smoke round (nudge, nudge, wink)” is along the lines of the imaginary prohibition of firing at personnel with the M2 .50 cal Browning MG.

  3. Countries which had an infantry anti-tank rifle at the beginning of WW2:

    Poland, Germany, the UK and Japan. Hungary bought Solothurns before joining the war.

    Countries which didn’t have one:

    – The USSR: production of PTRS and PTRD started after the German invasion.
    – Finland: received some rifles (Boys, wz. 35) during the Winter War, but production of the Lahti rifle started after the end of the Winter War.
    – Norway, the Netherlands, Belgium and France had no AT rifles in 1940
    – Italy: no rifles in July 1940, some Solothurns bought later in 1940
    – Yugoslavia and Greece had no AT rifles, except for the ones brought by British troops to Greece.
    – the US: no AT rifles, but tripod-mounted version of the M2HB .50 cal machine gun was in service and effectively used against Japanese light tanks and German light armored vehicles. One of the original design goals of the M2 was anti-tank use.

    • “Countries which didn’t have one(…)USSR”
      False, 7 October 1939 «14,5-мм противотанковое ружье обр. 1939 г» was adopted, it is known as Противотанковое ружье Рукавишникова образца 1939 года:
      http://weaponland.ru/load/protivotankovoe_ruzhe_rukavishnikova_obrazca_1939_goda/145-1-0-846
      original plan called for 50 examples in 1939 and 15000 in 1940, however in that time there was expectation that Red Army will face tanks with at least 60 – 80 mm, so such weapon would be useless, additionally there were technical problem with design itself, so production was halted, however improvements were in process and was tested in June 1941 with positive results, nonetheless after outbreak of Great Patriotic War, it was decided not to introduce new weapon in such situation. Produced AT rifles were used during Battle for Moscow.
      Basic data:
      Self-loading AT rifle
      cartridge: 14,5×114
      length: 1775 mm (barrel: 1180 mm)
      mass: 24 kg
      capacity: 5 rounds
      muzzle velocity: 1010 m/s

      • As I said, excepted was to be at least 60 – 80 mm, which lead to serious consideration of dropping 45 mm AT gun from production. 57 mm ZiS-2 was to enter production.
        Heavier armoured vehicles were also excepted to be encountered, so to not became in hopeless situation weapon with bigger armor-piercing ability was designed, namely 107 mm AT cannon M-75 (107-мм противотанковая пушка М-75), see photo here: https://topwar.ru/37743-opytnaya-protivotankovaya-pushka-m-75.html
        It was designed to penetrate 165 mm armor @ 30 deg. (Soviet style, 0 deg = vertical) @ 1000 m, muzzle velocity was 1020 m/s (18,8 kg shell) though it manage to only go through 160 mm (however, limitation was in not durable enough shell, so it is possibly could be done afters rework), combat-ready mass was 7500 kg.

      • Prototypes don’t really count, pre-series production is debatable. How many were produced before June 1941?

  4. Original warhead of the bazooka was based on the anti tank rifle grenade.They should have designed a more capable round to take advantage of the new weapons capabilities.The Germans copied the bazooka but went for larger 88mm from the beginning.

    • Originally, the Bazooka round was conceived as a rifle grenade, but it was too heavy to be fired from a rifle. Several ideas for launching it were proposed, the most interesting probably being using the M2HB .50 MG as a launcher with a blank round. (The Germans would do something similar with their 3.7cm PaK 36 a few years later, with an outsized bomb slipped onto the muzzle, except they actually used it in combat- not to their gun crew’s satisfaction.)

      The rocket launcher was the brainchild of Col. Leslie Skinner of Army Ordnance, with design work by Maj. Clarence N. Hickman and Lt. Edward G. Uhl. (NB; both Hickman and Uhl were prewar members of the American Rocket Society, in fact Hickman had been one of the founders of same.) The project actually began in 1940 when data on the new “Mohaupt warhead” (the hollow charge round) reached Ordnance, and proposals for a method of delivering it were requested. One result of this was of course the M9 rifle grenade. Skinner proposed a rocket launcher to fire a round with a more powerful warhead to a longer range.

      The first prototype was literally made of sections of downspout tubing, with an ignition system consisting of an adapted electric doorbell switch and flashlight batteries. The twin pistol grips and shoulder stock of the launcher were adapted from an M1921 Thompson SMG. Oddly, this gave it a more “finished” appearance than the later early production version, om which the stock as simply cut from 2″ thick planking.

      It was demonstrated at Frankford Arsenal (where it was developed) in April 1942, and in June was demonstrated to higher ranks at Aberdeen proving Ground in June ’42, when it managed ten hits out of twelve attempts on a moving tank at 150 yards. Incidentally, the early sight consisted of nothing more than a ring-and-post made from some wire lying on a workbench.

      Skinner and Uhl later went on to be the supervisors of the program that resulted in the 4.5in bombardment rocket, used in tremendous numbers as both a surface-to-surface and air-to-surface weapon during the last two years of the war.

      Source;

      Von Braun, Wernher, with Frederick I. Ordway. History of Rocketry & Space Travel, 3rd ed. New York; Thomas J. Crowell Co., 1966, 1975. PP. 94-97.

      cheers

      eon

  5. One “limitation” of man launched rocket propelled weapons is that the rocket has to be finished burning by the time it leaves the tube or it “cooks” the operator.

    Apparently one problem with the Bazooka was that in cold weather the rocket would not be completely exhausted when leaving the tube, I had a Tech Officer in Military School who had facial scars from firing a Bazooka in cold weather, the face shield usually supplied with the weapon was not available.

  6. The super bazooka is DE-ACTIVATED! Well dabnabit, you had my hopes up.

    Now, what am I’m going to with the basement full of bazooka rockets Uncle Clovis left for me?

  7. (Voluntary) Weapon of choice scenario in some fictional world:

    Setting: West Königsberg airport, HQ of a private aerial security firm
    Personnel in briefing room: 1st Patrol Squadron “Silver Fox” and the local airport security platoon.

    Pilots and soldiers, we have an emergency. Golden Goose, our rescue transport, has suffered critical damage and crew injuries due to sustained harassment while flying west over terrorist-claimed territory. The plane is now sitting in one of the hangars with the crew and passengers recovering in sick-bay. Our client, who is a nuclear physicist fleeing the terrorist organization, his family, and all his research notes, must NOT fall into the terrorists’ hands. Sadly for us, the terrorists in question have armor and light air support from a neighboring rogue fascist state to escort their own vehicles as they charge towards our base. Our host country’s nearest military base is over 100 km north of this base, so don’t expect immediate support.

    Enemy information:

    14 Mi-24PN gun-ships
    12 armored vehicles: 4 T-34-76’s, 2 Panther Ausf. A’s, 1 Tiger 1 Ausf. H, and 5 M8 Greyhounds.
    20 pickup trucks full of bad guys and their guns, and anti-air missiles

    Weather conditions: 5 km/hr west wind, heavy rain just stopped an hour ago
    Terrain conditions: Very muddy on the plains to the east, all enemy ground forces must come uphill to capture our base

    Available equipment:

    1. O-2 Sky Master (customize weapons on your hard-points)
    2. UH-1C Iroquois gun-ship (customize weapons here too)
    3. 10.5 cm Panzertod
    4. Panzer IV Ausf. H (only one on hand)
    5. ASU-57 or Marder III Ausf. M (all are operational and loaded)
    6. M20 Super Bazooka
    7. Bofors L/60 naval quad mount
    8. crates of anti-tank mines
    9. Maxim MG-18 13 mm machine gun
    10. 12.8 cm Flak-40 Zwilling or Pak-43/41 battery
    11. Or per the usual, screw the budget and add your favorite toys to this list!

    Disclaimer: This activity is completely voluntary. You don’t have to participate. Please keep any and all criticism of this post humane and free of foul language.

    Thank you,

    Cherndog

    • “11. Or per the usual, screw the budget and add your favorite toys to this list!”
      This time, I need some effort to found vehicles fitting for that need – able to counter three types of threats:
      a) helicopters (low-altitude AA defense)
      b) tanks (AT defense)
      c) soft-skin vehicles
      I considered Air Defense Anti-Tank System (ADATS) as used by Canadian Army, as it is supposed for a) and b), it also able to destroy c) but as it lacks any other weapon, would need to deploy rocket for that, when number or rockets is limited, also I am not sure if guiding system can be used against said pick-up trucks, smaller than tanks and AFV.

      Best fit, which I manage to fit was Flugabwehrkanonenpanzer Gepard
      https://en.wikipedia.org/wiki/Flakpanzer_Gepard
      which is armed with 2 Oerlikon 35 mm autocannons, each firing 550 rpm.
      Towed version of such armament also exist, named Oerlikon GDF.
      As name imply (Flugabwehrkanonenpanzer = Air defense cannon [armed] tank) it should be able to destroy helicopters, as APDS shell also exist it should have chance against armored vehicles, while I don’t know penetration for that particular gun, Oerlikon GDF query in English Wikipedia gives following data for APDS: 375 g shell @ 1440 m/s, navweaps site has query for 35 mm/1000 KDG Millennium GDM-008 which has data for APDS-T: 380 g shell @ 1440 m/s for penetration of 90 mm vertical armor @ 1000 m. I don’t know if is that same cartridge, but penetration should be similar, so it should suffice to destroy mentioned armored vehicles, frontal armor of “Panther Ausf. A’s(…)Tiger 1 Ausf. H” but side armor might penetrated.

      Older vehicles which should also work, are ZSU-57-2 with twin 57 mm and its NATO counterpart – M42 Duster (twin 40 mm) or yet older M19 Multiple Gun Motor Carriage (also twin 40 mm). Obviously to be effective against tank it must be equipped with AP shells.
      ZSU-57-2 fired BR-281 penetrating 110 mm @ 500 m and 100 m @ 1000 m of vertical armor (data gathered with Soviet method)
      For M42 Duster I have not penetration data, only information that M81 Armor Piercing with Tracer (AP-T) existed.

      • After some research I found data for 40 mm M81 shell, which are available here:
        https://drive.google.com/file/d/0B7wq5_b1e4MoRjYzUzIxRDl4SEE/view
        (there are data for other calibers too)
        no direct DISTANCE vs PENETRATION chart is available, however it might be acquired from chart.
        At Page 83 there is DISTANCE (YARDS) vs SHELL VELOCITY chart, indicating that:
        -at distance 1000 velocity is 2100
        -at distance 500 velocity is 2450
        -at distance 100 velocity is 2700
        At Page 85 and Page 86 are charts SHELL VELOCITY vs PENETRATION (INCHES), for homogeneous and face-hardened steel respectively, taking vertical armor we can read that
        -at velocity 2100 penetration is 1.7″ and 1.65″
        -at velocity 2450 penetration is 2.2″ and 2.15″
        -at velocity 2700 penetration is 2.55″ and 2.4″
        Data gathered via method called NAVY CRITERION

        • So considering that data, M42 Duster would probably have serious problems with penetrating “T-34-76(…)Panther Ausf. A(…)Tiger 1 Ausf. H” especially frontally, but shot in side also might fail.
          More relevant would be other data, for velocity I gave above, face-hardened steel and ANGLE OF INCIDENCE equal 45 degree::
          -at velocity 2100 penetration is 1.2″
          -at velocity 2450 penetration is 1.55″
          -at velocity 2700 penetration is 1.85″
          this does not look good against T-34 (1940) armor has hull sides armor 40 mm thick, with angle of 40 degree from vertical, same for Panther tank. Penetration possible, but with good hit and limited distance. Tiger I is in reality not go.
          Also from above linked material M81 and M81A1 are AP-T shells. However maybe there was some more advanced and capable armor-piercing (APDS? APCR?) shell for M42 Duster created later (linked document is dated JULY 1950)?

    • The best fit for this would be MANPADS and ATRLs, backed up by-don’t laugh- mortars and GPMGs or HMGs. Plus infantry riflemen and DMs, naturally.

      The Stinger proved to be effective vs. Hinds in Afghanistan in the Eighties, and more advanced shoulder-fired weapons should still be so. Note that those Hinds will have to get low and close for effective use of their weapons without risking “own goals”.

      The AFVs in question are older and relatively weakly armored by modern standards. Up-to-date ATGWs like Javelin would make short work of them. Even unguided light assault weapons like the AT4 (U.S. M136)recoilless gun, while not quite up to dealing with modern MBTs, would be an unpleasant surprise for tanks that are fifty years out of date.

      Having taken down the CAS and armor, you’re left with the “technicals”. 7.62 NATO GPMGs make an unholy mess of pickup trucks, even with improvised armor, .50 Brownings even more so, and any mounting HMGs (the Toyota with a 12.7mm DShK was the iconic vehicle of the Somali gangs)can be whacked up front with any Javelins left over. If you have some AT4s handy, so much the better (and more cost-effective).

      Once they unarse the vehicles and go to ground (and they will), continue MG fire and start dropping mortar rounds on them. Heavy on the Willy Pete, if you have some prox-fuzed airburst frag, so much the better. Plus small-arms engagement to catch any “leakers”; emphasize early take-out of any Mother’s Son waving an RPG around. (Sniper detail along with anybody who looks like a Fearless Leader.)

      Mop-up as usual.

      cheers

      eon

      • So if I were to fit rocket pods and Minigun pods to the Cessna O-2, would it be useful against the Hinds assuming I pulled a “Dicta Boelcke Dive” from the sun’s direction? And I assume we’d would have to launch at least 20 planes for this to work.

        • “rocket”
          But which rocket?

          “Minigun”
          According to https://en.wikipedia.org/wiki/Mil_Mi-24
          Mi-24 fuselage is heavily armored and can resist impacts from 12.7 mm (0.50 in) rounds from all angles. The titanium rotor blades are also resistant to 12.7 mm rounds. The cockpit is protected by ballistic-resistant windscreens and a titanium-armored tub.
          So I heavily doubt in 7,62×51 weapon effectiveness.

          • 70 mm rockets, to answer your first question. And nobody who flies attack choppers expects to get anti-armor rockets from above and behind, let alone a salvo of rockets plus bullet spam into the rotors.

  8. Odd that, after the example of the panzerfaust and all the Russian RPG versions, the U.S. never seems to have considered a shaped-charge launcher that didn’t require fitting the projectile into a tube. The panzerfaust was upgraded during the war since it didn’t need to fit an external launcher. RPGs would seem to offer more flexibility for projectiles for the same reason.

    • The panzerfaust wasn’t “upgraded” per se , the launcher tube diameter and length were different for the different versions ( 30k, 30, 60, 100 and 150 )

      • The number on a Panzerfaust was supposedly its effective range in meters. PF 30- 30 meters, PF 60- 60 meters, and so on.

        One of my uncles who was a Sherman troop CO in the ETO said that the usual range for a Panzerfaust ambush by Volkssturm or Hitler Youth was about ten yards, maximum. The Panzerfaust may have theoretically had an effective range of 30 or 60 meters, but in terms of accuracy, it could miss a Sherman at any range much beyond 20.

        Just as well for the Sherman. The Panzerfaust 30’s hollow-charge warhead was quite capable of punching in one side of the Sherman’s fighting compartment and out the other in a 90-degree side contact. You didn’t want to be sitting in the path of the “jet” in-between.

        cheers

        eon

        • Panzerfaust klein (Faustpatrone) and Panzerfaust 30 were the most common variants until late 1944 and the former stayed in production until the end of the war. Both had a nominal effective range of 30 meters against stationary targets. At such range hitting a moving target required an experienced operator. In Finland soldiers were taught to fire at moving targets at ranges from 10 to 20 meters, which would keep the time of flight below 1 second and leading the target fairly simple. That is, if they received proper training. Many didn’t in summer 1944, and effective use of the weapon had to be learned the hard way.

          Panzerfaust 60 had a muzzle velocity of 45 km/h, so hitting moving targets at up to 40 meters should have been relatively easy. It is possible and even likely that the Volkssturm and Hitlerjugend did not receive proper training in using the weapons and therefore fired at shorter distances with the PF 60 than strictly necessary.

    • Well,the US has not developed a domestically designed HEAT launcher after the 90mm M67 recoilles rifle was introduced in the early 1960s. The SMAW used by the USMC is based on the Israeli B-300 and the US Army currently uses the M3 Carl Gustav. The main advantage of rear (or “breech”) loading launchers is that the round can be loaded somewhat faster by the assistant. They can also utilize the recoilless principle and have a relatively high muzzle velocity (and accuracy) and good effective range.

      Weapons with an “overcaliber” warhead such as the RPG-7 and Panzerfaust 3 utilize a hybrid system, which has a a recoilless launching charge and a rocket sustainer motor. They tend to have a lower average projectile velocity and are more susceptible to crosswinds. The rocket motors also require high quality manufacturing in order to make them accurate in flight, although these days that is a relatively minor concern due to advantages in precision manufacturing.

      • Clarification: modern launchers with a larger-than-launch tube warhead have a hybrid propulsion. The German WW2 Panzerfausts and the RPG-2 were “pure” recoilles guns. They also had a relatively low muzzle velocity and short effective range.

  9. It sounds like I am the only one in the room with any real-life experience with the super bazooka. A few things to know;
    —Yes, a gas mask is pretty necessary, especially on a cold day, but just how cold? Best not to guess
    —Yes, they do too have a kick, just not a bad one. About the same as an M14.
    —-No, they’re not notably accurate. (I was selected as the Bazooka guy solely because I successfully managed to bounce a rocket off a vintage unmoving Sherman on the first bounce. Range was no more than 50 meters. Since I was the only one that connected with the tank, the ruling LT declared it close enough. Blue rounds are non-exploding practice projectiles. The motors certainly are live, though. Don’t do like I did and pick it up before it cools off. Duh. Always interesting policing up slightly used artillery shells.
    We theorized nobody had ever calibrated the optical sight. It would have been most discouraging had we had to deal with enemy tanks.
    But fortunately this was in Oklahoma.

    • As an addendum, they do not go “whoosh” like a movie sound effect. People are always surprised when they’re exposed to a military rocket launch . “WHAM!” Is more like it. And then you wonder if you hit something, you look up and there it is, slowly meandering about halfway there. Neither speedy nor reassuring.

  10. On the topic of Bazookas, does anyone have any pictures of the M18 Bazooka? According to Wikipedia it’s an experimental version made from aluminum alloy that was ordered in late summer 1945 but cancelled at the war’s end. I thought it was neat that it only weighed 4.8 kg compared to the previous variants which typically weighed around 6-8 kg.

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