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Bofors 40mm L/70 anti-aircraft gun

The 40 mm/70 was designed to replace the Bofors 40 mm/60 Model 1936 twin mountings with single mounts by doubling the rate of fire (ROF). The L/70 first emerged in 1947 and entered service in 1951. The Bofors 40mm L/60 was replaced by the L/70 version with a longer barrel, higher rate of fire, belt feed options (instead of the standard clips) and sundry other detail improvements to make an already outstanding automatic cannon even better. The Bofors L70 40 mm auto-cannon has a cyclic rate of 320 rounds per minute and an effective range of 4000 meters against both airborne and ground targets.

Newer, faster-firing versions of this weapon are still in production by Breda as well as Bofors. Today's The 40mm Mk 4 Naval Gun is significantly lighter and more affordable than earlier versions of the system. Though an impressive AAA gun in the late 1940-1960 time frame, the value of such weapons has decreased since then with the increasing sophistication of stand-off weapons.

The Swedish firm of Bofors is famous above all for the seemingly immortal 40mm automatic cannon. Bofors was purchased by United Defense which was in turn bought by BAE Systems. The undertakings of Aktiebolaget Bofors-Gullspang was the representative of iron industries which had been in continuous activity since the fourth decade of the 17th century, as far back as 1646. They remained in comparative insignificance for two hundred and thirty years until considerable extensions were made about 1870 that brought the works into some prominence. The Aktiebolaget Bofors-Gullspang was established in 1873 and adopted and maintained a continuous career of progress and improvement, and they soon owned works at Skjagersholm, Bofors, Bjorkborn, Bjorneborg and Gullspang.

The difficulties, the cost, and, in some instances, the danger of forging great blocks of steel made it a matter of moment to discover some method whereby the gases in the iron might be removed and a homogeneous steel produced. Such a method was discovered in 1870, and had been perfected at Terre-Noire. The Bofors Ironworks were the first Swedish works which had procured the Terre-Noire patent, and thus the first producers of this kind of steel in Sweden; and the method had a special interest to those assembled by the fact that guns of Bofors steel had been manufactured with the most satisfactory result, Sweden would very soon make her own guns.

By the late 19th Century the Swedish authorities considered the Bofors guns as reliable as those heretofore purchased from Armstrong and Krupp. Certainly a careful consideration of the sterling physical qualities developed by the Bofors steel, and their subsequent confirmation in actual, exhaustive trial, must greatly encourage all who believe in the thorough investigation of the feasibility of casting steel guns. Armor plates were cast at Bofors up to 20 tons in weight and are, if necessary, bent cold in a 1,000-ton hydraulic press to any desired curvature. Projectiles were also made at Bofors; but undoubtedly the most prominent work of the ordnance factory is connected with guns. These they make of various calibres, including 10 inch and a 4.4-inch quick-firing gun. the Bofors-Gullspang company also make the guncarriages, limbers, implements, ammunition wagons, etc., and that Bofors guns, projectiles and armour plates have been submitted to the severest tests and have acquitted themselves well, as shown by published reports of such trials.

The Bofors 40mm gun is one of the outstanding designs in light artillery it was originally designed in 1932, and is still in use today with only minor modifications. The Bofors 40mm gun was the most widely used antiaircraft piece of World War II. The Swedes began the guns development in 1928 and fielded the first units in the early 1930s. It could fire a two-pound shell to an effective range of 1,500 yards at a rate of 120 shots per minute. The world took notice when the British ordered the weapon in 1937, and, by 1939 the Swedes delivered the Bofors to 18 countries and concluded production licenses with 11 others.

Swedish Bofors 40 mm guns saw extensive action throughout World War II serving both sides. Both sides manufactured and used Bofors during the war. The Germans used a wide variety of light flak guns including a truck-mounted 40 mm Bofors. The US Navys interest in the Bofors 40 mm gun began in the fall of 1939; and, in late August 1940, guns and equipment arrived in the United States (fig. 32). Tested in September, the Bofors guns proved superior to both the US 37 mm and the British two pound (pom pom). The US government signed a contract in June 1941 and installed the first 40 mm Bofors aboard ship early the next year. The US Navys 40 mm guns, the everpresent Bofors, accounted for one-half of the Japanese aircraft destroyed by ship guns after October 1944.

The M42 "Duster" entered US Army service in 1953 and saw extensive action during the Cold War period. An evolution of the earlier M19 Gun Motor Carriage, the M42 consisted of twin 40mm Bofors guns mounted atop the new M41 "Walker Bulldog" light tank chassis. The vehicle's primary armament, the 40mm cannons, fired a variety of ammunition ranging from high explosive shells to heavy slugs at a rate of 120 rounds per minute per barrel, or a total of 240 rounds per minute. The heavy recoil and report from the guns kicked up a great deal of dust, giving the M42 its nickname.

Following tests in 1955, the US Army dropped its quadruple .50-caliber guns. The dual 40 mm guns lingered on in service into the early 1960s before being transferred from the Regular Army into the National Guard. Army studies in the mid-1950s indicated that guns could not provide adequate protection against the expected threat and that guided missiles would be more effective for the role of air defense in forward areas.

In the early 1980s, the US Army sought a mobile, all-weather system that would overcome these shortcomings. After rejecting the German Gepard, the Army believed that it could get what it wanted quickly and cheaply by combining several bits of existing equipment. After competing with General Dynamics, Ford Aerospace won a contract in May 1981 for the Division Air Defense or M247 Sergeant York. It would use an M48A5 tank chassis, twin 40 mm Bofors guns, and radar (APG-66) from the F-16. Problems with manufacturing, weight, reliability, and radar increased both time and cost.

In addition to numerous SAMs, the Royal Navy retained guns to protect against air strikes, such as the Bofors 40mm L/60.

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Page last modified: 05-05-2013 18:42:20 ZULU