Cruisers and cruiser actions

For main battery fire power, I would rank the Baltimores at the top. Why not Pensacola, Takao, Mogami, or Myoko (the ten-gun ships)? Pensacola fired a light shell, and her FC system was not up to later standards. The Japanese ships also fired a light shell, the shell itself was very poor against FH armor, and the gun operation was far slower than intended. On the other hand, Baltimore was the only class to have the super-heavy shell. Her broadside was 3015 lbs, greater than Takao's 2775 lbs.
Or you could pick the Deutschlands, which were official reclassed as heavy cruisers during the war. They had a 3968-lb broadside, not to mention the 15cm secondaries.
The weakest "heavy cruiser" would be Krasny Kavkaz, but that's not really fair of me. The little Almirante Brown had a broadside of 1200 lbs. The Furutaka types and Britain's "Cathedrals" would be next, I guess.
All the US wartime cruisers had twelve 5in DP guns except the Atlantas that had sixteen. British cruisers didn't have 5in guns; their heavy AA gun was 4in. The Didos came on line with 5.25in guns, but these were pretty bad as AA weapons; two units had 4.5in guns, which were actually superior.
Algerie certainly deserves attention among the best treaty ships. Personally I'd put Wichita maybe a touch above her. The only Japanese ships which were close to the treaty tonnage figure were the Furutaka types. If Portland deserves consideration, then New Orleans certainly does.

 

Thank you for correcting my mistake with the British 4-inch AA. Do you have a comparison of those cruiser's broadside weight by any chance?
For instance Portland's 9 x 8 inch guns versus Belfast's 12 x 6 inch guns, etc? What was the best DP guns in the war? The American 5-inch? how does the British 5-inch and Dido's 5.25 inch compare?

 

You can find shell weights and other data for lots of guns here:
http://www.geocities.com/kop_mic/
The only 5in guns in British service were American. The major British DP guns were 4in, 4.5in, 4.7in, and 5.25in. If that seems like a lot of different guns, then you'll understand why the British are often faulted for the proliferation of like-calibered guns and the logistical problems that resulted.
The American 5in/38 was the best DP gun of the war. This was a remarkable weapon system, and I don't believe any foreign counterpart comes close. Arguably the second best was the US 5in/25.
Britain's 4.5in was their best DP gun, and quite good. My only comlaint is that was not very rapid-firing. The 4in gun was capable of rapid fire, but guns of that size cannot compare with the shell weight of DD-caliber weapons.
The Japanese had a good 5in gun and a high-performance 10cm gun. The latter was especially good, though again, it had a small shell. It also suffered from absurdly high barrel wear.
The German 105mm gun, for all its complexity, was average. The Italians had a wonderful 90mm gun which, unfortunately, turned out too complex for its own good.

 

RM Medium calibre guns

http://www.quarry.nildram.co.uk/MCGWW2.html

MEDIUM CALIBRE GUNS OF THE ROYAL NAVY IN WORLD WAR II

© Anthony G Williams

This is a modified and extended version of an article which first appeared in Warship World, Winter 1988 issue

Most naval guns in the Second World War can be divided into three categories. These were: small-calibre weapons of up to 40 mm, which had fully automatic loading and firing cycles and were used almost exclusively as anti-aircraft weapons; large-calibre guns of 6in (152mm) or more for surface action, which had power loading systems as the ammunition was too heavy for easy manhandling; and medium-calibre guns which were manually loaded and often dual purpose, ie designed to be used against both aircraft and surface targets. After the end of the First World War the Royal Navy procured such guns in no fewer than four different major calibres - 4in, 4.5in, 4.7in and 5.25in (102mm, 114mm, 120mm and 133mm) - and in the case of 4in and 4.7in, in more than one version, requiring different ammunition.

These medium-calibre guns can themselves be divided into two types; those with fixed ammunition (ie shell and case handled in one unit) and those with separated ammunition with the shell and case carried separately to the loading tray. The choice made by the weapon designer between fixed and separated ammunition was determined by assumptions about the maximum weight which the loading numbers could be expected to manhandle. This was not quite the simple decision that it might appear as a weight which could easily be managed in favourable conditions was a different matter in North Atlantic winter storms with a cold and tired crew. Considering its vast experience the RN made some surprising errors in its choice of new equipment of this type.

The 4in and 4.7in calibres were traditional ones in the RN, and saw service in various versions in the First World War. Many of these older guns were still in service in World War 2, such as the 4in Mk IV L40 (the L40 referring to the calibre length, i.e. the barrel was 40x the calibre or 160in long) and Mk V L45, and the 4.7in Mk V. The 4in Mk V actually remained in production into WW2 and was installed in both high and low angle mountings.

After WW1 new guns were introduced. The 4in Mk XII and XXII were L40 submarine guns while the 4.7in Mk VIII was an L40 gun on a high-angle AA mounting - the only one in this calibre to use fixed ammunition, with a 45lb (20.4kg) shell - fitted to the new battleships Nelson and Rodney plus four other ships. More significant was the 4.7in Mk IX L45, fitted in single low-angle mounting. Equipped with a gunshield giving partial protection to the crew, this was the standard destroyer weapon throughout the 1930s and early 1940s. The 4.7in Mk XII was ballistically similar but fitted to a twin mounting in the 'Tribal', J', 'K' and 'N' Classes of destroyer. Both guns used separated ammunition with a 50lb (22.7kg) shell and could be fired at around 12 rpm (rounds per minute). They were perfectly satisfactory weapons against surface targets but the size and recoil distance restricted the maximum angle of elevation, at first to only 30º, later to 40º and eventually to 55º. Even in later versions they were therefore of limited use as anti-aircraft weapons.

Next to arrive were the 4in Mks XVI and XXI L45 (the latter being a lightened version) which were mainly fitted in the Mk XIX twin mounting, which achieved an elevation of 80º for true AA performance. A fixed round of ammunition weighing 65lb (29.5kg) - including a 35lb (15.9kg) shell - was used and a rate of fire of 12 (later 16) rpm per barrel could be attained. The mounting was highly successful and was used as the primary gun armament of a few destroyers, many escort vessels, some AA cruisers and minelayers and as the secondary armament of cruisers. The 4in Mk XIX L40 was also introduced, in a single mounting with 60º elevation, mainly for fitting to frigates and other escorts.

Work commenced in the 1930s on the design of new dual-purpose guns for aircraft carriers and light cruisers and as the secondary armament of new and refitted battleships and battlecruisers. It was at this point that the Navy's judgement went seriously awry. It was estimated that the maximum ammunition weight for fast manhandling was about 90lb (40.8kg) and two new calibres were designed accordingly; a 4.5in L45 using a fixed round of 90lb - the shell weight being 55lb (25kg) and a 5.25in L50 with separated ammunition and a shell weighing 80lb (36.3kg).

The 4.5in (which came in three marks, all virtually identical) was initially produced in twin mountings with an elevation of 80º. Three different patterns of twin mounting were used; the Mk II BD (between decks) was fully enclosed by a gunhouse and designed for aircraft carriers and reconstructed battleships and battlecruisers; the Mk III UD (upper deck), open to the rear, was relatively little used while the late-war Mk IV was a fully enclosed turret mounting. Ships so equipped included the refitted old battleships Queen Elizabeth and Valiant and the battlecruiser Renown (all with ten mountings), the Ark Royal and Illustrious class aircraft carriers and the Battle class destroyers (which had the Mk IV). Later in the war the 4.5in was also fitted in single mountings to some destroyer classes in place of the 4.7in but again the elevation could not exceed 55º. It is hard to understand why this gun was designed in the first place as its performance was only marginally superior to the well-established 4.7in and its production was obviously costly and caused ammunition supply complications.

The 5.25 in was only produced (for shipboard use) in a twin enclosed mounting offering an elevation of 70º. It was used in the Dido Class light AA cruisers (4 or 5 mountings) and the King George V Class and Vanguard battleships although it was also planned for the Hood as a part of the postponed refit. The Vanguard was fitted with modified mountings with a larger gunhouse.

The problems with the new calibres arose as wartime experience revealed that the maximum weight which the loading numbers could handle comfortably was much lower than 80-90lb and the weight of the 4.5in and 5.25in ammunition caused serious difficulties. This was subsequently remedied in the 4.5in by separating the shell from its case and its rate of fire was increased to 15 rpm. However, initially nothing could be done about the 5.25in (not helped by its cramped gunhouse) which could reportedly manage a rate of only 7-8 rpm instead of the designed 10-12, a failing which significantly reduced its AA effectiveness. The problem was not remedied until the introduction of the improved mounting in HMS Vanguard, which achieved the intended rate.

There was one further development early on in the war, the introduction of the 4.7in Mk XI, an L50 gun which fired a 62lb (28kg) shell of more streamlined design than the old 50lb type. This was only fitted, in a huge twin gunhouse, to just twelve destroyers of the 'L' and 'M' Classes. With a maximum elevation of 50º it was mainly intended for surface fire. It is again very hard to imagine that the development of yet another new gun in this class was worth the cost and supply problems.

With the benefit of hindsight it could be argued that the 4.5in, 5.25in and 4.7in L50 should never have been developed and that the Navy should have concentrated on producing more of the 4in and 4.7in L45. The 4in twin was little heavier than the 4.7in or 4.5in single and destroyers could therefore have been fitted with four mountings. The high-angle capability of the 4in Mk XIX, combined with the total rate of fire of 96-128 rpm (compared to 48 rpm of the four-gun 4.7/4.5in ships) would have produced vastly superior AA capabilities. However the RN preferred the heavier 4.7/4.5in shells for surface action despite the AA limitations of this weapon and the fact that the 4in ships could actually have thrown a heavier weight of fire (3,360-4,480lb per minute compared to 2,400-2,640lb) and obviously stood a much better chance of hitting a target through sheer volume of fire. Unfortunately it was not realised before the war that aircraft and even fast torpedo boats posed far greater threats than the enemy destroyers which the guns were intended to counter.

The 4.7in could have been fitted into the same high-angle twin mountings as the 4.5in and, given improved ammunition with the 62lb shell, could have outperformed the newer gun. Indeed, its performance would not have been too far from the 5.25in, yet each mounting would have been significantly lighter, giving the option to save weight or fit more mountings. If mounting weight alone is considered, the Didos could have been fitted with six mountings for the same weight as four 5.25in, giving a rate of fire of 144 rpm instead of 60 and a weight of fire of about 9,000lb per minute rather than 4,800. The new battleships could similarly have been fitted with twelve instead of eight mountings. Even if (taking other factors such as space and manning into consideration) the number of mountings remained the same, the weight as well as rate of fire would have been usefully increased. The AA performance would therefore have been greatly improved and against surface targets the slight loss of individual shell weight would have been more than compensated by the increased volume of fire.

Is it fair to criticise the Navy for decisions made at that time? Certainly the RN was not alone in underestimating the importance of AA fire (although the USN did much better with its 5in L38 DP gun and - of even greater importance - an effective DP director). However, it is difficult to defend the proliferation of calibres and weapons or the misjudgement over optimum ammunition weights.

HOME PAGE

 

awsome summary, I don't think we need to read anymore books after reading your post.
What do you think of the rapid-firing 8-inch gun that was developed by the US navy for the Des Moines cruisers at the end of the war, its rate of fire (10 rpm) was ridiculous for guns of that caliber.

 

Des Moines! She is completely above all other heavy cruisers. It's not just her guns. They're the most obvious feature, but the ship is also exceptionally well protected. A quote from FLEETS OF WORLD WAR II: "In one minute, Des Moines could hurl more than 30,000 lbs of metal at the enemy; this rates her in the same category with the Richelieu class battleships." Now, this doesn't mean she can take on a modern battleship with a good chance for victory, but it does indicate the level of destruction she can inflict on ships vulnerable to 8in shells. And if there ever was a heavy cruiser that had a chance to outslug a battleship, it was Des Moines.

 

I agree, Des Moines is the climax of the gun-cruiser design. Although many WWII battleships had thick armor that were designed to protect their vitals from enemy shells of similar caliber (i.e. 15 or 16-inch), I have no doubt that 90 of the 8-inch shells per minute raining down from the Des Moines, if on target, will wreak terrible havocs upon any battleships.

 

I'm surprised no-one's mentioned the American 'Alaska' class. Despite displacing over 30,000 tons and carrying nine 12inch guns, they were classified as cruisers and have been described as follows:

"they were, in effect, heavy cruisers finally unencumbered by the Treaty limits of 8 inch guns and a maximum dsiplacement of 10,000 tons."

Tony Williams: Military gun and ammunition website and Discussion forum

 

Or they were only battlecruisers built by US. USN didn't consider them as heavy cruiser, hence no CA but instead CB. On the other hand, they didn't have same CC -prefix like Lexingtons.. [I'm having problems here with my english skills, be patient, please]
I have to admit that ship having 9x12" guns, 30000 tons displacement, over 800 feet lenght and 5-9" belt armour does sound more like battlecruiser than heavy cruiser.

During world war 2 there were some other ships that can't easily put to any previus ship classing. (still problems with english here...).
Like twins (S&G), were they battleships or battlecruisers? Or rebuilt Kongos, were they still battlecruisers? I believe its quite fruitless to argue what these actually were. Being battleship, battlecruiser, heavy cruiser etc doesn't change ship at all, they were what they were, no matter what label we put to them.

 

I've specifically avoided the Alaskas because no one knows exactly what to make of them. In fact, I classify them in the same grouping as the Scharnhorsts: big ol' wastes of steel.
Alaska showed some features common to cruisers of the time and others common to battleships. I feel no great compulsion to consider them battlecruisers, and I'll be just as happy to call them second-class battleships. Why not? That's how I usually view the Scharnhorsts and Dunkerques.
I don't see much point in trying to distinguish between BB and BC for most designs after the Washington Treaty.

 

It would definitely wreak havoc with the battlewagon's superstructure, if nothing else.

 

I recently found out that the Japanese TONE class cruisers had all of their gun turrets forward of the superstructure, ala the British NELSON class battleships. Was this a good idea for a cruiser? BTW, the book I got my info from says that there are no known photographs extant of either TONE or her sister ship CHIKUMA; does anyone here know of any?

 

Yes, there certainly are photos of Tone and Chikuma.
Having four turrets all forward was not a good idea. While this freed the spaces aft for floatplane operations, the Japanese themselves never really liked the Tones, and the next CA project was based on Suzuya.

 

Do you have a site for these photos? BTW, in fairness, the book I referred to was published in 2001, so the author may not have known of their existence.

 

Japanese Cruisers of the Pacific War by Lacroix and Wells, published in 1997, has half a dozen good, clear photos of these ships, plus others that are too blurred to show much detail. The Americans themselves had plenty of opportunity to photograph Tone, which lay wrecked in a Japanese port at war's end.
Here's Chikuma.
http://www.history.navy.mil/photos/sh-f ... ikuma2.htm
I believe all four of these shots are from American sources.

 

Thanks, Tiornu.

 

That's a big if. A hail smaller shells might riddle non essential parts of a battleships structure but the really important stuff will be shielded by armor far too thick for a cruiser to penetrate at a sane range. Finally the first direct hit a battleship scores stands an excellent chance of blowing a cruiser to kingdom-come.

Were I a betting man I wouldn't be inclined to put money on any cruiser surviving serious attention from a capital ship.

 

Thanks for bring this threat back into action, I love sea actions.

I disagree with your assessments. The most heavily armored part of the battleships are the gun turrets (typicall 12-20 inch), and then the belt armor and barbettes (typically 10-12 inch). These should be fairy safe against 8 and 9-inch shells. But don't forget that the deck armor of battleships are only half as thick (excet Yamato), thus 8 or 9-inch shells fired from long distance plunging down at a steep trajectory will have no trouble punching through the thin deck armor and wreaking havocs beneath.

Just look at the Bismarck, its thick belt armor made it hard to sink, but it didn't take much to reduce it to a flaming hull.

And no, a cruiser can never equal the firepower of a capital ship, that was never my point.

 

Only Japanese and American cruisers would have much chance to drop an 8in shell through the deck of a modern battleship. They were specialized for anti-deck work, but even they would need extreme range.

 

If I really had to be on a cruiser going up against a battleship I would want to be on HMS "Giantslayer" Norfolk.