Military Review

40-mm anti-aircraft gun Bofors L / 60

40-mm anti-aircraft gun Bofors L / 60

After the end of World War I, many countries in service had 37-mm Maxim-Nordenfeldt automatic anti-aircraft guns and 40-mm Vickers automatic anti-aircraft guns.

Both systems had a similar pattern of operation of automation on the principle of using the recoil energy in the short course of the barrel.
The world's first 37-mm automatic cannon was created by American X. Maxim in 1883 year. In general, by its design, it was an increased in size widely known machine gun.

All mechanisms 37-mm machine mounted in the casing and box. The casing guided the barrel when firing and was a reservoir for the coolant, and the spring was pressed into the same fluid. The excess recoil energy is absorbed by the hydropneumatic buffer.

Used for the supply of cloth tape on 25 shells. The weight of the projectile is about 500 g. A cast-iron grenade with a ground impact tube, a canister having a 31 bullet or a remote grenade with an 8-second tube were used as projectiles. Firing Rate — 250-300 rds / min.

The Vickers machine gun was a lightweight and somewhat simplified Maxim machine with water-cooled barrel. The changes made it possible to reduce the size of the box and the weight of the machine compared to Maxim.

40-mm Vickers automatic gun

Tools of both types were used mainly in navydue to need weapons in clear water for cooling stems, significant weight (400-600 kg) and design complexity.

These machines have proven to be very effective means of defense. A comparatively powerful projectile had a good destructive effect, often the struck plane was falling apart in the air. Automatic fire allowed to create a sufficient density of fire and sharply increased the likelihood of hitting the target.

Common drawbacks of automata were: the complexity and high cost of manufacture, complex cleaning and preparation for shooting, the use of cloth tape and the long path of the cartridge when feeding from the tape, low reliability.

Soon due to rapid development aviation these guns ceased to satisfy the demands of the military. It required a more reliable and long-range weapon for firing at air targets.

In the summer of 1930, Sweden began testing a new 40-mm automatic gun, which was developed by Viktor Hammar and Emmanuel Jansson, designers of the Bofors plant.

Automatic guns based on the use of recoil force according to the scheme with a short recoil of the barrel. All actions necessary for firing a shot (opening the bolt after the shot, extracting the liner, cocking the drummer, feeding the cartridges into the chamber, closing the bolt and lowering the hammer) are performed automatically. Manually carried out the aiming, pointing guns and feed clips with ammunition in the store.

Interest in the new system was shown by the Swedish Navy. The official tests for the Swedish fleet began on March 21 of the year 1932. At the end of the test, it was named Bofors 40-mm L / 60, although the barrel was actually the length of 56,25 gauges, and not in the 60, as the name suggests. High-explosive 900g projectile (40x311R) left the barrel at a speed of 850 m / s. The rate of fire around 120 rds / min, which increased slightly when the gun did not have large elevation angles. This was due to the fact that gravity helped the mechanism for supplying ammunition. Those. own weight shells helped in the reloading mechanism.

The practical rate of fire was 80-100 rds / min. The shells were loaded with clips on the 4 cartridge, which were inserted manually. The gun had a practical ceiling near 3800, with a range of more than 7000.

The automatic gun was equipped with a modern at that time aiming system. Horizontal and vertical gunners had reflex sights, the third member of the calculation was behind them and worked with a mechanical computing device. The sight was powered by a 6V battery.

However, the recognition of the new system, as is often the case, did not happen at home. Swedish naval sailors believed that 20-25-mm were the optimal calibers for anti-aircraft guns, so they were in no hurry to order less rapid-fire 40-mm anti-aircraft guns.

The first customer of the L60 anti-aircraft guns was the Dutch fleet, which installed 5 twin installations of this type on the De Ruyter light cruiser.

Light cruiser "De Ruyter"

In the future, the Dutch fleet bought a few more batches of anti-aircraft guns to arm ships. The guns were mounted on a special stabilized installation, developed by the Dutch company Hazemeyer (Hazemeyer). At the end of the 1930s, this installation was the most advanced short-range anti-aircraft weapon in the world.

The weapons of the Swedish Navy came into service after testing and trial operation only in 1936. The first versions of the 40-mm guns were used on submarines. The barrel was shortened to 42 calibers, which reduced the initial velocity of the projectile to 700 m / s. When this weapon was not used, the trunk rose up, and the weapon was retracted in a waterproof cylindrical case. The shortened weapon was used on submarines of the Sjölejonet type, on which it was the only deck gun powerful enough to provide effective fire on small vessels.

In the 1935, the land version of this tool appeared. It was installed on a four-wheel towed "cart". In the case of urgent need, shooting could be conducted directly from the gun carriage, i.e. "Off the wheels" without additional procedures, but with less accuracy. In normal mode, the frame of the carriage fell to the ground for greater stability. The transition from the “traveling” position to the “combat” position took about 1 minutes.

With an installation weight of about 2000 kg, its towing was possible with an ordinary truck. Calculation and ammunition while located in the back.

The tool was popular with foreign customers. Belgium became the first buyer of anti-aircraft guns. Argentina, Belgium, China, Denmark, Egypt, Estonia, Finland, France, Greece, Norway, Latvia, the Netherlands, Portugal, the United Kingdom, Thailand and Yugoslavia were among the countries that purchased Bofors L60 anti-aircraft guns at the end of the 30s.

Bofors L60 was produced under license in Belgium, Finland, France, Hungary, Norway, Poland and the UK. In very significant quantities Bofors L60 was produced in Canada and in the USA. More than 100 thousand 40-mm Bofors anti-aircraft guns were manufactured worldwide by the end of World War II.

Anti-aircraft 40-mm guns produced in different countries were adapted to local conditions of production and use. Components and parts of guns of different “nationality” were often not interchangeable.

The greatest difference from the "original" had British-made anti-aircraft guns. The British did a great job of simplifying and cheapening guns. To speed up the guidance of fast-moving and diving planes, the British used the mechanical analog computer Major Kerrison (AV Kerrison), which became the first automatic control system for anti-aircraft fire.

Kerrison Mechanical Analog Calculator

The Kerrison device was a mechanical calculating device that allows determining tool pointing angles based on the position and movement of the target, ballistic parameters of the gun and ammunition, as well as wind speed and other external conditions. The resulting guidance angles were automatically transmitted to the instrument's guidance mechanisms with the help of servomotors.

The calculation of three people, receiving data from this device, rather easily and with good accuracy suggested a weapon. When using this device, the calculator controlled the guidance of the gun, and the calculation needed only to charge the gun and fire. The original reflex sights were replaced by simpler ring-mounted anti-aircraft sights, which were used as duplicates.

In this modification, the gun QF 40 mm Mark III has become the army standard light anti-aircraft installation. This British 40-mm anti-aircraft gun had the most sophisticated sights of the entire Bofors family.

However, in battles it was discovered that the use of a Kerrison device in some situations was not always possible, and besides, it was necessary to supply the fuel that was used to power the generator. Because of this, in most cases, when shooting, most often they used only conventional ring sights, without using any target designation and calculations of corrections for lead time, which greatly reduced the accuracy of shooting. Taking into account the combat experience in 1943, a simple trapezoidal Stiffkey device was developed, which moved the riflescopes for introducing corrections when firing and was controlled by one of the anti-aircraft gunners.

The British and Americans using the Bofors L60 created a series of ZSU. Open turret anti-aircraft guns mounted on a chassis tank Crusader. This self-propelled anti-aircraft gun was called Crusader III AA Mark I.

ZSU Crusader III AA Mark I

However, the most common British 40-mm ZSU was "Carrier, SP, 4x4 40-mm, AA 30cwt", created by mounting an anti-aircraft gun on the chassis of a conventional four-wheel Morris truck.

ZSU "Carrier, SP, 4x4 40-mm, AA 30cwt"

In the United States, Bofors was mounted on modified 2,5 t chassis of GMC trucks CCKW-353.

These self-propelled units were used to support the ground forces and provide quick protection against air attacks without the need for stationary installation on the ground and deployment of the system into a combat position.

After the fall of Holland in 1940, part of the Dutch fleet went to the UK, and the British had the opportunity to familiarize themselves in detail with the Hazmeyer marine installations. 40-mm Hazmemeier Dutch naval anti-aircraft installations differed favorably in combat and service performance from the British 40-mm "pom-pom" company "Vikkers".

Firing 40-mm Vickers anti-aircraft guns

In 1942, the UK began its own production of such plants. In contrast to the "land" anti-aircraft guns, most of the marine guns had water cooling.

For the American and British fleets, a large number of one, two, four, and six-barreled anti-aircraft guns, including radar-guided ones, were developed.

In the US Navy, this weapon is considered to be the best anti-aircraft gun of the Second World War, 40-mm anti-aircraft guns were the most effective against Japanese kamikaze aircraft. As a rule, one direct hit of an 40-mm fragmentation projectile was enough to destroy any Japanese aircraft used as a “flying bomb”.

The effective range of 40-mm anti-aircraft guns was twice as high as that of 12,7-mm machine guns and 20-mm anti-aircraft guns.

At the end of the war, the Bofors almost completely supplanted Oerlikon automatic cannons on large warships.

Despite the fact that Germany had its own anti-aircraft 37-mm automatic machine "Rheinmetall", 40-mm Bofors L60 were actively used in the armed forces of Germany and its allies.

Captured “Bofors” captured in Poland, Norway, Denmark and France were used by the Germans under the designation 4-cm / 56 Flak 28.

Abandoned Polish 40-mm Bofors L60 anti-aircraft gun against the background of a crushed column

Some of these Norwegian-made guns were used on submarines and on the cruisers Admiral Hipper and Prince Eugen.

In Finland and Hungary, these tools were manufactured under license and used throughout the war.

Finnish 40-mm automatic Bofors L60 anti-aircraft gun on an armored train

In Japan, an attempt was made to launch the Bofors L60 into serial production after several British air-cooled installations were captured in Singapore. The Japanese anti-aircraft gun was designated 4 cm / 60 Type 5, but it was not produced in significant quantities due to the weakness of the production base.

But the most massive copy of the Bofors L60 was the Soviet "37-mm automatic anti-aircraft gun mod. 1939 G. ”also known as 61-K.

After the failure of attempts to launch mass-scale production at the Moscow Region Plant named after Kalinin (No. 8) of the German 37-mm automatic anti-aircraft gun “Rheinmetall”, due to the urgent need for such an anti-aircraft gun, at the highest level, it was decided to create an anti-aircraft gun based on the Swedish system which by that time received worldwide recognition.

37-mm automatic anti-aircraft gun obr. 1939

The gun was created under the direction of M. N. Loginov, and in 1939, it was put into service with the official designation “37-mm automatic anti-aircraft gun mod. 1939.

According to the leadership of the gun service, his main task was to fight against air targets at distances up to 4 km and at altitudes up to 3 km. If necessary, the gun can be used for firing at ground targets, including tanks and armored vehicles.

Mastering it in production went with great difficulties, the percentage of marriage was great. Before the beginning of the war, 1500-mm anti-aircraft guns were released around 37. True, their quality left much to be desired, there were very frequent delays and failures when shooting.

On 22 June 1941, the Red Army had an 1214 "37-mm automatic anti-aircraft guns arr. 1939 g. During the 1941 battle of the year, anti-aircraft guns suffered significant losses - until 1 September 1941, the 841 gun was lost, and in just 1941 a year - 1204 guns. Huge losses were hardly compensated by production - on 1 January 1942, there was about 1600 37-mm 61-K anti-aircraft guns available.

In the initial period of the war, 37-mm anti-aircraft guns entered the artillery brigades of anti-tank defense and anti-tank regiments, as regular weapons for fighting tanks. In 1941, 320 37-mm anti-aircraft guns were sent to anti-tank units. In 1942, anti-aircraft guns from anti-tank artillery were removed.

A significant amount of 61-K was captured as trophies by German troops. In the Wehrmacht, these guns got the 3,7 cm Flak 39 (r) index and were used in battles - so, by January 1944, the troops had 390 of such guns.

37-mm automatic anti-aircraft gun 61-К captured by the Germans

During the war years in the USSR the 40-mm Bofors L60 were massively supplied by the allies. In terms of its ballistic characteristics, the Bofors 40-mm cannon was slightly superior to the 61-K - it fired a somewhat heavier projectile at close initial speed. In 1940, in the USSR, comparative tests of Bofors and 61-K were conducted, according to their results, the commission noted the approximate equivalence of the guns.

61-K during the Great Patriotic War were the main means of air defense of the Soviet troops in the front line. The tactical and technical characteristics of the gun allowed it to effectively deal with the enemy’s front-line aviation, but until 1944, the troops experienced an acute shortage of automatic anti-aircraft guns. Only at the end of the war our troops were adequately covered from air strikes. On 1, January 1945, there were about 19 800 61-K guns and Bofors L60.

After the end of World War II, 37-mm anti-aircraft guns 61-K and 40-mm Bofors L60 participated in many armed conflicts, in a number of countries they are still in service.

In the US, the Bofors L40 60-mm assault rifle is used on Lockheed AC-130 "ganships" for firing at ground targets.

Reloading 40-mm Bofors L60 guns on board AC-130

These anti-aircraft guns became the most "belligerent" they for all the years of use were shot down more aircraft than all the other combined anti-aircraft guns.

A further development of the Bofors L60 system was the 40-mm anti-aircraft gun Bofors L70, which uses the more powerful 40 × 364R munition with a slightly lighter projectile to 870 g, which increased the initial speed to 1030 m / s.

40-mm Bofors L70

In addition, the gun carriage and recoil mechanism was redone. The first copy of the new weapon was made in 1947 year. In November, 1953, this gun was adopted as a standard NATO anti-aircraft gun, and soon it began to be produced in thousands of series.

During the years of production, several variants of this anti-aircraft gun were created, which differed in the power scheme and sighting devices. The latest modifications to this gun had an 330 rate of fire per minute.

In addition to the towed anti-aircraft gun Bofors L70 used in self-propelled anti-aircraft installations: VEAK-4062 and M247 Sergeant York.

During the years of production, several variants of this anti-aircraft gun were created, which differed in the power scheme and sighting devices. The latest modifications to this gun had an 330 rate of fire per minute.

In addition to the towed anti-aircraft gun Bofors L70 used in self-propelled anti-aircraft installations: VEAK-4062 and M247 Sergeant York.

ZSU M247 Sergeant York

In the Swedish army, this weapon is armed with the CV9040 infantry fighting vehicle, in order to place it in the tower it was necessary to turn the weapon "upside down". Under this weapon, developed new ammunition, including: subcaliber and fragmentation with remote blasting.

BMP CV9040

Bofors L / 70 is used as the main instrument on the South Korean BMP K21.


Bofors L / 70 cannons are also still used in various naval installations for arming patrol and rocket boats and small displacement combat ships.
The most modern of those where the artillery part of L / 70 is used is the Italian Zak "Dardo" (production "Oto Melara") intended for anti-missile and air defense of the ship.

High-explosive fragmentation projectiles with ready striking elements in the form of 600 tungsten balls and a non-contact fuse are used for firing at PKR.

After many years, technical solutions implemented in the 40-mm guns of the Swedish company Bofors in the 30-s of the last century are effectively used today. There is no doubt that this system will meet its centenary anniversary in the ranks.

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  1. inkass_98
    inkass_98 26 June 2014 10: 39
    Swedes are able to do weapons, you can’t say anything. A reliable tool that spawned a whole line of anti-aircraft guns.
    1. Maksim...
      Maksim... 26 June 2014 13: 00
      Yes, and the American guidance system, and even with radars! Ummm!
  2. igordok
    igordok 26 June 2014 13: 20
    Off topic.
    Why does the "commander" have a helmet (helmet) different from the helmets (helmets) of loaders? For what reasons is it made large? In addition to the fleet, it seems to have come across in land air defense.
    1. Andrey591
      Andrey591 26 June 2014 14: 50
      Under it are headphones, communication.
  3. ka5280
    ka5280 26 June 2014 13: 45
    Bofos L / 70 is still in service with the Latvian army, based in Lielward at the former Soviet airfield, about 20 units.
    1. peter mechkaev
      peter mechkaev 26 June 2014 22: 07
      At one time, at one training ground I met about 800 anti-aircraft guns, model 39, on conservation .. many passed the Second World War. In the 90s they were loaded onto platforms and taken away. According to rumors, they were sold to the Middle East. Is it true .. I don’t know ..
      1. Bongo
        27 June 2014 05: 25
        37 mm anti-aircraft guns arr. 1939 years were also actively used during armed conflicts in the territory of the former USSR. So during the First Chechen fighters used them against Russian aviation.
  4. archi.sailor
    archi.sailor 26 June 2014 14: 30
    Quote: inkass_98
    Swedes are able to do weapons, you can’t say anything. A reliable tool that spawned a whole line of anti-aircraft guns.

    Bofors created and is testing a 100-mm shipborne assault rifle (gun mount). They will be adopted (I mean Sweden)
  5. sivuch
    sivuch 27 June 2014 17: 15
    Who else would say when this gun received shells with an RL fuse.
    By the way, about shells in general could have been more detailed
    1. 52
      52 2 July 2014 19: 35
      Think for yourself, where in such dimensions to cram the RL fuse, and the price of this "wunderwafe"! laughing
  6. voyaka uh
    voyaka uh 27 June 2014 19: 31
    I was very interested to read. And the photos are great. Knew nothing about
    the history of anti-aircraft guns.
  7. Homecoming
    Homecoming 21 March 2018 20: 39
    Such guns in the 45th could protect Tokyo and other Japanese cities from the nighttime bombardment of General Lemey.