When used on a ship, to fire at attacking planes, was it fired pretty much like a 20mm.? It was the Eye/Experience of the gunner that guided the round to the target.? There wasn't a proximity fuse small enough to fit in a 40mm....was there.? Thank You
I was at the Pensacola Museum about ten years ago and was standing next to a vet who was explaining how the 40mm worked to his son. He showed him how it was tied into the central fire directors and how they could be over ridden to fire under local control. He was very specific about many details and I asked him when he had last seen one of them. He said, "About sixty years ago." Ship gun fire-control system - Wikipedia EDIT: MK 51 Fire Control System[edit] Mark 51 Director with Mark 14 (40 mm) Gun Sight The Bofors 40 mm anti-aircraft guns were arguably the best light anti-aircraft weapon of World War II.,[30] employed on almost every major warship in the U.S. and UK fleet during World War II from about 1943 to 1945.[30] They were most effective on ships as large as destroyer escorts or larger when coupled with electric-hydraulic drives for greater speed and the Mark 51 Director (pictured) for improved accuracy, the Bofors 40 mm gun became a fearsome adversary, accounting for roughly half of all Japanese aircraft shot down between 1 October 1944 and 1 February 1945.[30]
Depends on the mounting. The US twin and quad 40mm were generally controlled from the Mark 51 and later types of director as described in Dave’s post. But there were other types of mount including single hand worked mounts based on those used by the Army. Then the RN had their own versions including the twin Hazemeyer (with director and radar built into the mount) and the single “Boffin”, which was a twin 20mm Mk.V converted to carry a single 40mm barrel. These were generally fitted with a gyro gunsight, similar to the one which was at the core of the Mk 51 director. Loads of information here USA Bofors 40 mm L/60 Model 1936 - NavWeaps
OK.... Thanks For my own reasons, i found this info to be of particular interest....... "It should be noted that the USN considered the original Bofors Model 1936 design to be completely unsuitable for the mass production techniques required for the vast number of guns needed to equip the ships of the US Navy. First, the Swedish guns were designed using metric measurement units, a system all but unknown in the USA at that time. Worse still, the dimensioning on the Swedish drawings often did not match the actual measurements taken of the weapons. Secondly, the Swedish guns required a great deal of hand work in order to make the finished weapon. For example, Swedish blueprints had many notes on them such as "file to fit at assembly" and "drill to fit at assembly," all of which took much production time in order to implement - there is a story that one USA production engineer remarked that the Bofors gun had been designed so as to eliminate the unemployment problems of the Great Depression. Third, the Swedish mountings were manually worked, while the USN required power-worked mountings in order to attain the fast elevation and training speeds necessary to engage modern aircraft. Fourth, the Swedish twin gun mounting supplied to the USA for evaluation was air-cooled, limiting its ability to fire long bursts, a necessity for most naval AA engagements. Finally, the USN rejected the Swedish ammunition design, as it was not boresafe, the fuze was found to be too sensitive for normal shipboard use and its overall design was determined to be unsuitable for mass production. US manufacturers made radical changes to the Swedish design in order to minimize these problems and as a result the guns and mountings produced in the USA bore little resemblance their Swedish ancestors. For example, all but the earliest US guns were built to English measurement units rather than to metric units. To give one additional example of the design differences made for USA produced weapons; the Chrysler Corporation redesigned ten components to suit mass production techniques and this was claimed to have saved some 7,500,000 pounds (3,402,000 kg) of material and 1,896,750 man hours during a year's production, as well as freeing up 30 machine tools for the production of other components. For ammunition, the fuze designed and produced in Britain was adopted as an interim measure by the USA, but this was considered to be of an unsafe design and unsuitable for mass production techniques. Fortunately, this fuze was almost immediately replaced by one designed by R.L. Graumann of the Naval Ordnance Laboratory. This fuze was simple in design and "ideally suited to mass production." The new fuze, designated as the Mark 27, was found to be 99.9 percent efficient in ballistic acceptance tests, a record not equaled by any other fuze of the time. Both the US Army and the British adopted this fuze for their own production lines. The USN estimated that the adoption of the Mark 27 saved some $250,000,000 during the war."
Reminds me of the old saying, "If you see any vices in a production factory they are not doing it right."
Found an online picture of the 40 mm I mentioned in my post. https://www.navalaviationmuseum.org/nnam/virtualtour/ It is in the "West Wing 1/8" menu drop-down. This museum is as good as the Air Force museum at Wright Patterson. There is one difference in that not all of the their plane are flyable although they are cosmetically better than new. I remember one early jet fighter that had been recovered from a 30 year stay in a NJ playground while filled with concrete. When they got done with it it looked perfect on the outside.
I do not know if it was actually anymore dangerous than any other job on deck, but....... when i watch WW2 Videos, and i see the loaders for the 40mm guns....one on each side.... it seems like they are just standing there, right in harms way, and ready to be shot or shrapped.
The two loaders with their back to the plane has always been the first thing I look at in this famous picture.
