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Naval Gun Projects

Spec

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RP1 said:
I'm not sure if it was here or on another forum, but I remember a discussion of a Rarden based remote control mounting proposed for the RN. Thanks to an old issue of the gleefully entitled "War Machine" (The 1980's, eh?) I have a few details.

"LS30R"
• Laurence Scott Defence Systems mounting
• RARDE 30mm Rarden automatic cannon
• Power driven and LOS stabilised
• Tests carried out by RN at sea on trials FF HMS Londonderry and on land at the Fraser Gunnery Range
• Hit a 2m2 target 80% of the time at ranges between 1000-1300m
• HE, APSE and APDS rounds
• LS30R was to replace 20mm and 40mm weapons, initially starting on OPVs
• Basic mounting can be used with 30mm Oerlikon KCB and Mauser Model F (LS30B and LS30F)
• -20 to +70 degrees elevation
• 6-22 rounds on-mount

This was the weapon DJ Brown used on a lot of his independent concept designs.

- RP1
Hm came accross this forum just generally browsing through google on some related stuff and this came up, cant add much to most of your discussions but I can certainly shed some light on this. The LS30R died literally dead no more it never went past the prototype. However no before it spawned a son the LS30B this then changed its name by deed poll to the DS30B just prior to entering service with the RN. Mainly down to a company name change as laurence Scott Defence systems is now MSI-Defence Systems ltd www.msi-dsl.com.

The DS30B has been around for 20 years now inservice with several navies. It now has a replacement the SEAHAWK linkage here

http://www.janes.com/events/exhibitions/dsei2007/sections/daily/day3/seahawk-family-nests-at-d.shtml

http://bp0.blogger.com/_JEyyV88-wp8/RxKRxzDBkrI/AAAAAAAAAK0/4qCrw8QIDmo/s400/ascg.JPG

The new Seahawk system has already undergone succesful trials onboard RN vessels as the ASCG, HMS Somerset has mentioned the trials in his Blog about halfway down.. He calls it the bushmaster.

http://hms-somerset-co.blogspot.com/search?updated-max=2007-10-22T07%3A09%3A00Z&max-results=7

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Longshaor

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Kugelblitz,

I seem to recall seeing a number of late WWII USN drawings with 37mm marked on them for the light AA guns. IIRC, the idea was floated to replace the 20mm Oerlikon with a derivative of the M9 37mm cannon used on PT boats, which was itself taken from the P-39 Aerocobra. Hope this helps.
 

Artie Bob

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I went through the USN gunnery syllabus in the mid-50s. IIRC, we were told that befor the end of WWII, Kamikaze attacks changed the philosophy os USN anti-aircraft gunnery. Against this type of attack, 20 mm and even 40mm were useless, what was required was a shell with sufficient kinetic energy to deflect the aircraft from a collision trajectory. For this reason, the 3"/50 dual mount was rushed into production to replace quad 40mm mounts (we were told it was essentially a drop-in replacement). I had the good fortune to train and live fire on a 40mm quad (first loader), 3"/50 (first loader), 5"/38 (second loader) and powder handler for the 16" main battery on an Iowa class ship which when I was on it was essentially in WWII trim (except all 20 mm mounts had been deleted).

Of course, that philosopy has since been revised several times, currently with the small caliber extremely high fire rate guns which are designed to defeat the threat with multiple high velocity strikes.

Best Regards,

Artie Bob
 

Longshaor

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Interesting. I recall reading (probably Friedman, but I'm not sure) that the move from 40mm to 3" was driven by the inability to manufacture a VT fuze capable of fitting in a projectile smaller than 3". The "plan" was to replace the quad 40s with the 3"/70 twin automatic mount on a 1-for-1 basis with the 3"/50 twin as a stand in until the development of the 3"/70 was completed. In fact the 3"/70 had a tortured development and only went to sea in about 8 ships. The progress in AA missile technology was a beter invenstment and the 3"/50 was seen as good enough.

Cheers
 

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On principles:
Deflecting a 10000lb aircraft+bomb travelling at 400ft/sec using a 2lb (40mm) or even a 15lb (3in) shot travelling at 2000ft/sec is a no-go. The 2lb shell has only 1/1000 of the momentum of the plane.
You need either a lucky hit on a control surface to do the deflection, or an explosive shell whose fragments disrupt the aircraft structure. Hence use a larger calibre, with a heavier shell. But the gun is slower-firing, and you need to get damage from near-misses, so no medium calibre AA is much use until the VT fuze ensures a near miss will detonate close enough for many shell fragments to hit the 'plane.
The aim is to blow the attacker apart sufficiently far away, not just to knock it off course. The 3in fires a shell 7 or eight times as heavy as the 40mm, and fires fast enough to put several times the weight of shell in the air compared to the good old 5in - especially if the comparison is with 90rpm L70 3in, though they took until well after the war had ended to get working. Modern small calibre guns are very rapid firing, fast enough to get many hits and so disrupt the structure.
The British 3in L/70 on HMS Tiger eventually worked quite well. The UK post-war rapid fire 5in never saw service. The objective was 70-90 rpm. The RN never got anything, but the army got a prototype Green Mace, which is in the Firepower Royal Artillery museum at Woolwich Arsenal. An awesome beast:
http://www.skomer.u-net.com/projects/greenmace.htm
 

RP1

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It should be noted that another kill method is for (small), energetic projectiles or fragments to cause deflagration / detonation of the warhead or rocket motors / fuel tanks.

RP1
 

smurf

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And hit the pilot, though that might be too late to stop a Kamikaze
 

cluttonfred

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I am reviving this thread from a couple of months ago with a question:

Why, in the naval or land-based context, does the shotgun concept seem to be rarely if ever to be used in anti-aircraft weapons?

Legality aside, no one would hunt a duck with an accurate, small caliber machine gun, so why don't close-in weapons systems targeting aircraft and missiles use, in effect, big shotguns? Even at modest velocities that seems more effective at putting up a "wall of lead" than an autocannon. Perhaps some sort of variable choke would allow adjusting the pattern for various ranges? It seems like that would substantially reduce the technical challenge of hitting a sea-skimming missile, yet I have never heard of it being used.

Enlighten me! ;)
 

red admiral

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I would think that the typical engagement ranges would reduce the accuracy and lethality of a small number of subprojectiles.

The Spanish Meroka weapon here is sort of similar but uses multiple barrels instead of one large one. Range is pretty short though.
 

RP1

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Re: Naval Gun Projects (Shotguns)

Why, in the naval or land-based context, does the shotgun concept seem to be rarely if ever to be used in anti-aircraft weapons?
Shotgun projectiles have been proposed for anti surface use:

http://www.dtic.mil/ndia/2003gun/steel.pdf

"5-Inch Shotgun Projectile", L Steelman, 2003

The AHEAD (Advanced Hit Efficiency And Destruction) rounds could be regarded as shotgun-esque, as they release pellets rather than casing fragments, and rely as much on the target velocity as the pellet velocity:

http://www.rheinmetall-defence.com/index.php?lang=3&fid=2177

Also, of course, the IJN developed 18 inch "sankaidan" incendiary shrapnel anti-aircraft rounds for the Yamato class vessels. These would explode under the target creating a cone of shrapnel. However, as noted below, they were not safe and exploded in the gun barrel.

http://www.navweaps.com/Weapons/WNJAP_18-45_t94.htm

A conventional shotgun cartridge, where the shot is released directly from the barrel, would be ineffective against most aerial targets due to the poor ballistics of the pellets - this is why shotguns are safer for hunting than, say, rifles, as the shot looses lethality very quickly. The pellets would thus have low penetration and subsequent internal effects on the target.

The shotgun projectile requires an increase in accuracy over a conventional fragmentation round, in that the cone of shot produced has to be pointing at the target - with a (roughly) spherical burst the round may be effective even if it is alongside the target.

RP1
 

Orionblamblam

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Mole said:
Legality aside, no one would hunt a duck with an accurate, small caliber machine gun,
Not necessarily true. I live within earshot of a waterfowl hunting area, and every now and then during duck hunting season I hear fully automatic weapons opening up. I too question the value of using an M-16 or an AK-47 to hunt ducks, but there it is.
 

tinlail

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Mole said:
I am reviving this thread from a couple of months ago with a question:

Why, in the naval or land-based context, does the shotgun concept seem to be rarely if ever to be used in anti-aircraft weapons?

Legality aside, no one would hunt a duck with an accurate, small caliber machine gun, so why don't close-in weapons systems targeting aircraft and missiles use, in effect, big shotguns? Even at modest velocities that seems more effective at putting up a "wall of lead" than an autocannon. Perhaps some sort of variable choke would allow adjusting the pattern for various ranges? It seems like that would substantially reduce the technical challenge of hitting a sea-skimming missile, yet I have never heard of it being used.

Enlighten me! ;)
I suspect the main issue is one of reloading speed. Since ducks rarely bomb hunters let another duck fly by is no great loss after downing the first one. As reloading speeds increase your weapon starts to take on the characteristic of a machine gun.
 

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smurf said:
And hit the pilot, though that might be too late to stop a Kamikaze
The equivalent of a CIWS causing missile warhead detonation is AA fire exploding a Kamikaze's bombload, yes? The difference is that in a missile, the warhead forms a significant proportion of vehicle volume, so that anything which can hit the vehicle is likely to detonate it; whereas the warhead (e.g. underslung 500lb bomb) forms only a small part, volume wise, of a diving A6M.

But a missile weighing several thousand pounds is a difficult target to stop in anyone's language, surely. I suspect that if the current US Navy had to face WW2 Kamikazes, most of the surface-to-air kills would be made by SM-2 or RIM-7.
 

RP1

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Interesting problem this. Putting fragment holes in an aircraft's wings won't unnecessarily cause it to miss it's target, unlike a missile where the control and lifting surfaces are quite small. Unless you can get a controlled fragmentation pattern a HE blast warhead might be preferable - the resulting loss of an entire control surface would be likely to make the Kamikaze miss its intended target. I note from designation-systems.net that the early USN SAM Lark used a HE warhead - perhaps that is why?

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Jemiba

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"..the resulting loss of an entire control surface would be likely to make the Kamikaze miss its intended target.."

It's a matter of the distance, at which the target, Kamikaze or missile can be hit and so a matter of
weapons range. If the target is too close, it won't need any more flight control, as it just will follow
on the ballistic trajectory and hit nevertheless. As I've read, that was exactly, what happened to a
lot of Kamikazes, which still hit the target, although wings and control surfaces were shot away and
the "guidance system", the pilot, probably already out of action. In consequence, the USN moved away
the 20mm AA guns from their ships, keeping only the 40mm, which proofed not to be effective enough,
too, to secure total disintegration of the attacker.
 

Demon Lord Razgriz

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Sorry to go slightly off topic, but does anyone have an idea what the caliber is going to be on a full-size Naval Rail Gun? I've looked and I can't find it.
 

sferrin

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Demon Lord Razgriz said:
Sorry to go slightly off topic, but does anyone have an idea what the caliber is going to be on a full-size Naval Rail Gun? I've looked and I can't find it.
I doubt they've progressed to the point that there's actually an answer to be had there.
 

smurf

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http://www.youtube.com/watch?v=y54aLcC3G74
that projectile looks to be about 4 to 5inch, and 5in is a US standard
 

JFC Fuller

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smurf said:
more naval material could shed light on DACR
I'm not sure it will!
There is a long and authoritative article "Post war cruiser designs for the Royal Navy `1946-1956" by George Moore in Warship 2006 (pp38 - 58). The background to the changes in design is money, and the changes from gun to missile armament. DACR gets several mentions, the last of which (a table of 1951/52 cruiser designs some with 6" and 3", some with 5", but all with 4 DACR) has a footnote:
DACR: Direct Acting Close Range - probably cancelled sextuple Bofors L70
No details, and none of anything other than the Bofors. George Moore is pretty thorough, and gives his ADM and DNC dept Work Book sources, and his article traces well the progress, or lack of it, with the larger calibre AA weapons of the period - 6", 3", and 5".
The sextuple Bofors L60 was mounted on HMS Vanguard, twins and singles elsewhere. The navy considered the L70 (which the army adopted rather than Red Queen) to replace their L60s but did not adopt it.
The impression I get from the first mention of DACR is that it was an acronym for a requirement for the post war cruisers, to supplement their 6" and 3" guns, rather than a particular design of weapon system. That requirement that might be most easily met by the sextuple L70 expected (in 1948) to enter service in 1957. Given the long lead time from 1948 to 1960ish before the relevant cruiser designs might be built, it could well have been a "see what turns up" approach, such weapon developments being very fluid at the time, but probably with a timescale hoped to be a little shorter. There are (good?) naval precedents for this approach. The Vickers 2pdr pompom was included in the armament of the cancelled 1921 G3 battlecruisers (with 6 or 10 barrels), although the County cruisers of 1927 had to wait 3 years for their definitive 8 barrelled version, fitting single barrelled guns in the meantime, and destroyers until the late 30s for their quad. A more recent equivalent to DACR would perhaps be the rush to mount Phalanx after the Falklands war.
Sorry to raise this thread from the depths but I have a quick question, is their a source for the sextuple Bofors L70 design and what stage of development did it reach?

I have always been fascinated by the sextuple L60 mount as it is one of the primary factors behind Vanguard having such an outstanding anti-aircraft fit and there is something quite awesome about, I would love to know more about the L70 version if there is any information out there?
 

sferrin

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RP1 said:
Just a quick one: Advert for the GAU-8 based "Satan" CIWS, from USNI Proceedings October 1985.

RP1
Looks like they combined the sensor and gun into Goalkeeper.
 

Lauge

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Orionblamblam said:
I live within earshot of a waterfowl hunting area, and every now and then during duck hunting season I hear fully automatic weapons opening up.
Wouldn't that most likely be the ducks returning fire?

Regards & all,

Thomas L. Nielsen
Luxembourg
 

TomS

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sferrin said:
Looks like they combined the sensor and gun into Goalkeeper.
The gun mount in Goalkeeper was actually a General Electric design (EX-83) and was proposed for quite a few different CIWS applications in the 1980s -- Goalkeeper, SATAN, SAGEM's SAMOS, VSEL's Sea Dragon (referenced earlier in this thread), and possibly more.
 

sferrin

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TomS said:
sferrin said:
Looks like they combined the sensor and gun into Goalkeeper.
The gun mount in Goalkeeper was actually a General Electric design (EX-83) and was proposed for quite a few different CIWS applications in the 1980s -- Goalkeeper, SATAN, SAGEM's SAMOS, VSEL's Sea Dragon (referenced earlier in this thread), and possibly more.
The one in the 2nd post in this thread is still my favorite. :eek:
 

RP1

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A note on the calibre of Rail Guns. I recently co-authored a paper on "The Impact of Integrated Electric Weapons on Future Warship Design" at INEC 2010 and dug up a lot of information on the on going EM Rail Gun projects (most of which are IEEE papers and so can't be disseminated here).

Calibre is a poor indicator of EMRG firepower and "flight mass" and muzzle velocity, together giving muzzle energy, are more normally used, since one aim is to achieve target destruction through kinetic energy effects alone. The most complete recent figures I have (from 2003) are a flight mass of 16.4kg, launch mass of 21.9kg (the projectile is launched in an insulating sabot and conducting armature), MV of 2000m/s and bore diameter of 146mm. The ~63MJ system frequently alluded to has a similarly sized projectile with an increased MV of 2500m/s. [1][2]

RP1

[1] 21. McFarland, J & McNab, I R, “A Long Range Naval Railgun”, IEEE Transactions on Magnetics, Vol. 39, No. 1, January 2003
[2] 25. Ellis, R, “Exploring the Possibilities of a Naval Electromagnetic Rail Gun”, 38th Annual Gun & Ammunition Symposium March 24 – 27, 2003
 

TomS

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sferrin said:
TomS said:
The gun mount in Goalkeeper was actually a General Electric design (EX-83) and was proposed for quite a few different CIWS applications in the 1980s -- Goalkeeper, SATAN, SAGEM's SAMOS, VSEL's Sea Dragon (referenced earlier in this thread), and possibly more.
The one in the 2nd post in this thread is still my favorite. :eek:
Nice gun, but that's not a relative of EX-83 at all. The 35mm case telescoped CIWS was based on the Phalanx mount, which is quite different from EX-83.
 

uk 75

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In a 70s pic of .U.S.N guns a 3" gun in spherical mount next to a mk 65. Need more info
 

thebig C

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Hey

Does anybody have any info on a Bofors 76mm naval gun. It was used by Norway on the Storm class patrol boats and Singapore on their Vosper FPBs. It possibly derived from a WWII aa gun. Anyway, it is very elusive and there are few references to it on the Net. It featured a very distinctive half-egg shaped turret. Going on the vintage of the vessels involved is it safe to assume that Bofors abandoned it in the 1960s to concentrate on the 57mm?

Also, and I might be dreaming this one:)), I have a vague recollection of reading about a new turret (possibly of intermediate calibre betweem Oto Malera 76mm and the French 100mm), in an illustration/mock up it sort of resembled an Oto Malera in that it was cylindrical but featured a much flater top. Am I dreaming?:p

C
 

TomS

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thebig C said:
Hey

Does anybody have any info on a Bofors 76mm naval gun. It was used by Norway on the Storm class patrol boats and Singapore on their Vosper FPBs. It possibly derived from a WWII aa gun. Anyway, it is very elusive and there are few references to it on the Net. It featured a very distinctive half-egg shaped turret. Going on the vintage of the vessels involved is it safe to assume that Bofors abandoned it in the 1960s to concentrate on the 57mm?
The post-war Bofors 76mm gun (TAK76) was one of the very few low-angle guns produced in that era, suitable only for surface fire. It's possible that it was derived from the M1927 anti-aircraft gun, but I doubt it given its low-angle only design. I believe it fired the same ammunition as the US 3-inch/50 gun. As you surmise, it was displaced by the SAK57 dual-purpose gun, which was heavier but far more versatile. I think I've got more info in one of my older reference books, but I'm getting ready to move, so it may not be accessible.
 

thebig C

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TomS said:
thebig C said:
Hey

Does anybody have any info on a Bofors 76mm naval gun. It was used by Norway on the Storm class patrol boats and Singapore on their Vosper FPBs. It possibly derived from a WWII aa gun. Anyway, it is very elusive and there are few references to it on the Net. It featured a very distinctive half-egg shaped turret. Going on the vintage of the vessels involved is it safe to assume that Bofors abandoned it in the 1960s to concentrate on the 57mm?
The post-war Bofors 76mm gun (TAK76) was one of the very few low-angle guns produced in that era, suitable only for surface fire. It's possible that it was derived from the M1927 anti-aircraft gun, but I doubt it given its low-angle only design. I believe it fired the same ammunition as the US 3-inch/50 gun. As you surmise, it was displaced by the SAK57 dual-purpose gun, which was heavier but far more versatile. I think I've got more info in one of my older reference books, but I'm getting ready to move, so it may not be accessible.
Hey Tom

Thanks a million for that. I could find very little info, and, it seems that this gun was used for relatively few applications. Perhaps because of the drawbacks you suggest.

C
 

Abraham Gubler

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thebig C said:
Thanks a million for that. I could find very little info, and, it seems that this gun was used for relatively few applications. Perhaps because of the drawbacks you suggest.
They weren't drawbacks but what it was designed to do. It was a gun to destroy other fast attack boats and was in the vein of the 6 Pounder (57mm) gun on British MGBs during WWII. At that time (the 50s and 60s) there were very few medium calibire (57-76mm) anti aircraft guns and all of them were usually huge. It wasn't until the Oto Gun (76mm) and the Bofors SAK 57 fielded in the mid to late 1960s that fast attack boats could carry a gun bigger than the Bofors 40mm for anti aircraft fires. So by the time demand for western fast attack boats really caught on the late 60s and 70s there were excellent dual purpose guns to arm for air defence and sinking other boats.
 

TomS

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thebig C said:
Thanks a million for that. I could find very little info, and, it seems that this gun was used for relatively few applications. Perhaps because of the drawbacks you suggest.
Found more in a copy of Jane's Naval Weapon Systems. Per Jane's, the gun was a private venture by Bofors begun in 1962, and was adapted from a 76mm/50 coast artillery gun, but modified to 3-inch (a very minor change in dimension) "because that ammunition was more commonly used by navies." The ammunition is described as a fixed cartridge weighing 11.3kg, which could mean it's not the US 3-inch/50 round, which apparently weighed 10.9 kg complete (however, I see some variation between sources). Muzzle velocity is 825m/s, nearly identical to the US round (2 m/sec difference).

The turret is fully automated, fed from a motor-driven hoist to a below-deck magazine with 100 rounds. Two loaders move ammo from the magazine to the 5-round feed drum, which in turn feeds the vertical hoist. From there, a transfer arm in the turret moves the rounds to the loading tray and the rounds are then rammed home. RoF is 30 RPM. Traverse was 350º with elevation limits of -10 to +30º. Range was credited as 6.8 nautical miles (12.6 km). The turret is roughly 1.5 m high, with a penetration below decks of 2.9 m. Total mount weight was 6.5 tons.

The image below is from Jane's, but I think it was probably originally from the manufacturer.
 

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Petrus

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TomS said:
the gun was ... adapted from a 76mm/50 coast artillery gun, but modified to 3-inch...
The Swedish used, if my memory serves me well, coastal guns in 75mm rather than 76mm calibre. They were automatic weapons as well and their cupolas seemed quite similar to those of the 76mm ship gun.

By the way, the drawing is really breathtaking. Thank you for posting it.

Piotr
 

TomS

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Makes sense. There was a Swedish 75mm/57 gun used mainly in fixed installations that was fielded in 1957; it seems a likely candidate for adaptation to US 3-inch/50 ammunition (basically similar velocity and shell weight, despite the minor caliber change). Probably the Jane's reference to 76mm is a typo or mistake.

http://en.wikipedia.org/wiki/7.5_cm_tornpj%C3%A4s_m/57
 

thebig C

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Hey TomS

Thanks for those posts!! Some great info there.

The start date for this project of 1962 is interesting because off the top of my head I can only think of a handful of vessel classes that used them. Namely, the Storm Class patrol boats and Sleipner Class corvettes of Norway and on the Vosper FACs of Singapore. They are all of 1960s vintage meaning that Bofors must have ceased marketing this weapon after just a few years.

When you look at the low ROF compared the Bofors 57mm mk i (developed around the same time early 1960s) and the slightly later (mid 1960s) Oto Malera 76mm its perhaps unsurprising that it was given the heave-ho! To say nothing about its lack of adaptability to different tasks as you have pointed out!

It is worth noting though that the imensely successful Oto 76mm of today is the second attemt. The original 76mm "allargato" gun was pretty unsuccessful, being ordered only by the Italian Navy. It does make you wonder though, given that Oto took a couple of attempts to get things right, if Bofors had persisted they might just have produced something excellent and really dominated the medium calibre market. Not exactly a pipedream when you consider so of the great guns they have produced!

Its probably a bad reference, but just look at the TAK120. It was developed, as with the TAK76, in 1962 as a private venture. It was only adopted by Finland (Turunmaa Class 1960s) and Indonesia (Corvettes early 1980s). In all likelyhood it was harmed by the Swedish decision to disgard all vessels larger then torpedo/missile boats from 1968 onwards. Anyway, it was 120mm and managed 80!! rounds per minute. A staggering rof for a gun of that vintage!

http://www.navweaps.com/Weapons/WNSweden_47-46_TAK120.htm

C
 

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It's interesting that the 120mm single also failed to gain much success (a couple of Finnish ships and three for Indonesia is all, IIRC). I suspect that it could not have been terribly reliable at full speed; most of the other extremely fast guns in that general size range had issues with jamming and were significantly derated.

I've had a conversation with some other folks and am now convince that the TAK 76 used US pattern 3-inch/50 ammunition. Tony Williams (Jane's Ammunition Handbook, among other things) says that Norway was making a 3-inch/50 round with Bofors-style designations that exactly matches the measurements of the US round.
 

cluttonfred

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That TAK120 had only ten ready rounds in two, five-round magazines? That seems pretty dicey if you have only five rounds per target type, even if they are big shells.
 

Petrus

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Mole said:
That TAK120 had only ten ready rounds in two, five-round magazines? That seems pretty dicey if you have only five rounds per target type, even if they are big shells.
Somewhere (a Polish magazine) I've read that those magazines were reloaded manually. Could you confirm this information?

Piotr
 

cluttonfred

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Per link in thebigC's post...

Sweden
120 mm/46 (4.7") TAK120
Updated 18 November 2006
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A fully-automatic weapon intended for large Fast Attack Craft (FAC). Developed on a private-venture basis from an anti-aircraft field gun. Uses a water-cooled barrel with a replaceable liner and a vertical-sliding breech block, which opens downward during recoil. The gun feeds alternatively from two magazines, one on each side of the barrel. Each of these magazines holds five rounds. This arrangement allows for two different kinds of ammunition to be loaded so that the gun can be immediately switched between ammunition types. The automatic loader uses a spring-powered rammer, which is cocked by the recoil forces.
 

TomS

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Jane's gives slightly different info about the TAK 120 L/46 ammunition supply. It says there were magazines on each side of the gun consisting of four compartments with five rounds each. These in turn supported a pair of feed tables, each holding six rounds. That's either 32 or 52 rounds on mount, depending on how you interpret it (4x5 total or 4x5 on each side). Those rounds could then be manually reloaded in 2.5 minutes by two human reloaders. The gun would have to return to a loading position for this evolution.
 
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