Did the USA ever pay for those guns?

Jonathan Beard's picture

Two of the most popular weapons used in World War II were the Oerlikon 20 mm automatic cannon, and the Bofors 40 mm automatic cannon. When the USS Missouri steamed into Tokyo Bay in 1945, she carried 49 20 mm guns and 80 40 mm. These guns were used throughout the USN, by the Royal Navy, and by the armed forces of several other countries, and on land and in the air, too. American factories produced both by the tens of thousands.

Oddly, neither weapon came from a belligerent. The Oerlikon was Swiss, and the Bofors, Swedish. It is my impression from some reading on this topic that the USA, at least, “pirated” these designs, modified them, and then mass-produced them during the war. After the war, did the USA pay millions in licensing fees or in some way compensate the Swiss and Swedish firms that had patented these designs?

Jonathan Beard


Categories: Query
Keywords: guns, WWII, Query

The U.S. Navy's Bureau of Ordnance (BuOrd) was the executive agent for both series of guns and post-war BuOrd did negotiate compensation with the Bofors and Oerlikon companies. Part of this came in the form of royalty-free use in future production of the many improvements developed by BuOrd and its contractors. Twenty-five years later I conferred with Bofors representatives on other matters and asked if the company felt satisfied that it had been treated fairly. They indicated that it did and that the study of the American methods had led them to substantial changes in their manufacturing operations.

In response to Mr Beard's request.

The Bofors Gun used by the US Forces in the 1939-45 War was the UK modified L/60 weapon from the original Swedish design and the Polish manufactured guns purchased by the UK, and its construction converted from metric measurement to Imperial (meaning the Universal system, not British Empire).

Its manufacture details were transferred to the USA as part of the Tizard Mission supply of British technology to the USA. See ZIMMERMAN David. Top Secret Exchange. The Tizard Mission and the Scientific War. Allan Sutton Publishing, Stroud, 1996.; this amplified by PHELPS Stephen. The Tizard Mission. The Top-Secret Operation that Changed the Course of World War II. Westhome Publishing, Yardley, PENN., but this text does not not give details of actual weapons systems such as these.

GANDER Terry J. The Bofors Gun. Pen & Sword, Barnsley, 2013., gives details of the modifications, and touches upon the supply to the USA of microfilmed plans and material specifications. A Royal Artillery major Instructor in Gunnery, and two Warrant Officer Master Gunners went to the USA to provide training for the usage of the gun system to the USN (and they also gave support to the Coast Artillery Corps anti-craft school). Civilian engineers and production specialists from The Royal Ordnance also went to the US to advise on production and actual manufacturing techniques.

In the USN service, the Bofors Company in Sweden signed a official licensing agreement in June 1941, for the unmodified Swedish manufacture, which did not cover the UK modifications. Under the terms of the Tizard Mission the UK modifications (nor the UK designed and developed ammunition were not paid for.

The 20mm Oerlikon was acquired for British Army service as a battalion level anti-tank gun, whilst its quality was recognized the Army held off to acquire a more potent weapon in the shape of the two pounder Anti-Tank Gun. Whilst The Royal Ordnance had purchased a manufacturing licence, and manufacturing plans from the parent company in Switzerland, the Royal Navy which did its own thing in regard to the purchase of weapons dealt directly with the Swiss company.

The RN had in the mid-1930's had invested a great deal of time and money in the Vickers Quad .5inch Machine Gun (similar in many ways to the even worse USN 1.1 Quad Heavy Machine Gun) which (its mount) proved inadequate against fast moving aircraft, and literally there was no money to spare for the Oerlikon to replace it. The then Captain Lord Louis Mountbatten, whilst not a Gunnery Specialist pushed in the 14 months before September 1939 to purchase the Oerlikon, many in the Gunnery Branch of the RN did comprehend the quality of the weapon.

In SEP 39, the First Sea Lord directed that the gun should be purchased, and whether not knowing that the Royal Ordnance had a manufacturing licence purchased guns directly from Switzerland. Only 109 guns were received in the UK from a order of 1,500 before the Fall of France, these weapons were constructed to metric standards, and never saw sea service, being used for land based ground air defence of RN facilities in the South of England.

Confusion reigns in regard to the subsequent manufacture in the UK, widely stated is that the Admiralty purchased a manufacturing licence from Oerlikon, and after the Fall of France had the design and manufacturing plans smuggled out to the UK. But, the History of the Royal Ordnance Factories In the 1939-1945 War, by the Ministry of Supply, tells a different story.

This being that the Royal Ordnance held a manufacturing licence pre-war, its engineers had converted from Metric to Imperial, and a substantial number of minor modifications had been made to the weapon to improve its combat effectiveness as a automatic weapon (in Army use it had been to be used purely in the semi-automatic role), and for the weapons modification for production. They coming into RN service at sea in early 1941, and manufactured under the original RO licence. A effective Drum Magazine was also developed.

The weapon's UK developed naval mount was totally different from the parent company's one, and the modifications made the weapon substantially different from the original weapon. The plans etc (including the Drum Magazine) were transferred to the USA in the third of the tranche of the Tizard Mission transfers (also RO technical support). It would appear from the the History of the Royal Ordnance Factories, that in the initial supply of US manufactured Oerlikon's were for use by the RN, and it would further appear (?) that US manufacture was under the auspices of the original UK licence.

For the US Army, again under Tizard six UK pattern 40mm Bofors and fire control equipment, with the UK designed 40mm ammunition were supplied. These under the same terms as the other Tizard supplies.

The vast number of M1 produced in the US Army and USMC for the main period between 1941 and 43 saw a certain number of minor modifications to the gun, but, these primarily for the mass production process for the thousands of sub-contractors employed in the manufacture of components. The US official histories make no mention of Royalties being paid to Bofors, again probably under the original UK licence (?) .