British 16 inch guns
- Thread starter steveburt
- Start date
Hmm - RN used only the 16 inch breechloading 45 calibre guns, didn't they? (from the 20s - with 2048lb AP shells).
Maybe it's a case of comparison to the more modern american 16 inch (45 and 50 calibre) guns, and not wanting them to share traits with the newer guns/ammunition. The guns on the Iowas, South Dakota and North Carolinas fired 2700 pound APC shells.
Maybe it's a case of comparison to the more modern american 16 inch (45 and 50 calibre) guns, and not wanting them to share traits with the newer guns/ammunition. The guns on the Iowas, South Dakota and North Carolinas fired 2700 pound APC shells.
That was the rationale for placing them at AP. My rationale for saying they should have the same level of "APness" comes mainly from a verification exercise with such well researched rules as GQ3 and others which credit the British 16" with broadly the same (or in some cases and in game terms exactly the same) armour penetrating qualities as the US guns. Since IIRC they used Nathan Okun's armour penetration prediction software and/or had the official penetration tables for the gns concerned to which they could refer (and I was a lazy sod and didn't want to go through the rigmarole myself) it seemed like a reasonable assumption (plus I know the guys that did the and I trust their opinions).
At the end of the day though its a judgement call and if the statting system uses a shell mass to determine penetration and the Brit one falls one side and the US shell falls the other then thats OK. There are other arbitrary cutoffs in VAS (as in most rules) which could be debated, but at the end of the day the designer has to make a call and then be consistent (or be as consistent as possible), so I'm broadly happy.
At the end of the day though its a judgement call and if the statting system uses a shell mass to determine penetration and the Brit one falls one side and the US shell falls the other then thats OK. There are other arbitrary cutoffs in VAS (as in most rules) which could be debated, but at the end of the day the designer has to make a call and then be consistent (or be as consistent as possible), so I'm broadly happy.
what gets me is the fact that all the US battleships seem to have super AP and radar, whereas none of the british fleet have super AP and half of the British ships that actually had radar aren't credited, simply because not all of the class shared that ability, for examle 3 out of the 5 Queen Elizabeths had radar by 1941, but none in the rules do (except in one scenario...).
in a way it just feels as if the US ships had their faults glossed over and the British ones were downgraded.
however, in a wider context, the US ships and the Japanese ships are pretty well balenced, also the italian/german ships balence pretty well with the British ones. They're all statted pretty well against their expected opponents.
At the end of the day, the rules do work and pretty well, but there is always room for improvement, and us being wargamers we'll always feel that our side is being let down in one way or another. I haven't yet seen anyone complain that the British are the only side with carriers as a skirmish option despite having fewer than anyone else, or that they seem to be excellently equipped with planes considering the state of the FAA when war broke out! All the countries have problems in their statting, but there are other perks they have which they might not have had in wartime.
in a way it just feels as if the US ships had their faults glossed over and the British ones were downgraded.
however, in a wider context, the US ships and the Japanese ships are pretty well balenced, also the italian/german ships balence pretty well with the British ones. They're all statted pretty well against their expected opponents.
At the end of the day, the rules do work and pretty well, but there is always room for improvement, and us being wargamers we'll always feel that our side is being let down in one way or another. I haven't yet seen anyone complain that the British are the only side with carriers as a skirmish option despite having fewer than anyone else, or that they seem to be excellently equipped with planes considering the state of the FAA when war broke out! All the countries have problems in their statting, but there are other perks they have which they might not have had in wartime.
Sturmgrenadier
Mongoose
Excellent, looks like the supplement may be the momentum that helps VaS pick up steam (pun intended) around here...
(It's kinda on the edge of popularity or obscurity at the moment)
(It's kinda on the edge of popularity or obscurity at the moment)
jbickley00
Mongoose
Well, ultimately this is about physics: force = mass times velocity.
The 16"/45 used on the Nelson class ships, used a relatively lighter shell, at a relatively high velocity, but ended up being a dissappointment. Thus the Hood, and the KGV class ships mounted the 15"/42.
It is hard to truly measure the impact of any of these shells on say 18" of belt armour at 20,000 yards, but if we want to draw a brightline between AP and super AP, the relative velocities and weigths provide a distinction.
In the super AP Category, there are only four classes of ships with Super AP: the Yamato, the Iowa, the North Carolina and the South Dakota.
The Yamato mounted 18.1"/45 guns fired a 1.460kg shell which had a striking velocity of 521 Meters per second at 20,000 meters. The armour penetration at 20,000 meters was 494mm of side armour.
The Iowa mounted the 16"/50 Mark 7 gun, which fired a 1225kg shell with a striking velocity of 497 meters per second at 22,860 meters, penetrating 441mm of side armour. At 18,288 meters, the penetration of the Mark 7 gun was 509 mm of side armour, so its performance is certainly on par with the Yamato's guns.
The SoDak and North Carolina classes mounted the 16"/45 Mark 6 gun, which fired the same 1225kg shell as the Mark 7. The striking velocity at 22,860 meters was 463 mps, with penetration of 382mm of side armour. At 18,288 meters the penetration is 448mm.
The British 16"/45 fired a 929kg round with a striking velocity of 453 mps second at 22,860 meters. Its armour penetration at this range was 261mm of side armour. At 18,288 meters, the penetration was 310mm.
As you can see, the Armour pentration on the British weapon is much lower than the american equivalents. The American Mark 6 weapon has superior pentration at 30,000 yards than the British weapon does at 20,000. This is why the British weapon does not get "Super AP." Clearly not all 16" weapons are created the same.
The 15"/42 used on the HMS Hood fired an 871kg projectile that had a striking velocity of 420 mps at 18,288 meters. The armour penetration at this range was about 279mm. Thus the Britich 16" shell is closer in performance to the British 15" shell than it is to the American's Heavy 16" shell. Thus the US battleships have Super AP and the british Nelson Class Ships are simply AP.
They did a good job with these rules. It may be that, out of fairness they give the brits a super AP ship. But doing this means that the Colorado Class and the Japanese Nagato Class also rate it. At that point the Hood has an argument for being super AP, and so does any ship with 15" guns. The British Queen Elizabeths would be Super AP, and the KGV would not.
I think the line is well drawn where it is. We don't want the Super AP classification to be meaningless.
The 16"/45 used on the Nelson class ships, used a relatively lighter shell, at a relatively high velocity, but ended up being a dissappointment. Thus the Hood, and the KGV class ships mounted the 15"/42.
It is hard to truly measure the impact of any of these shells on say 18" of belt armour at 20,000 yards, but if we want to draw a brightline between AP and super AP, the relative velocities and weigths provide a distinction.
In the super AP Category, there are only four classes of ships with Super AP: the Yamato, the Iowa, the North Carolina and the South Dakota.
The Yamato mounted 18.1"/45 guns fired a 1.460kg shell which had a striking velocity of 521 Meters per second at 20,000 meters. The armour penetration at 20,000 meters was 494mm of side armour.
The Iowa mounted the 16"/50 Mark 7 gun, which fired a 1225kg shell with a striking velocity of 497 meters per second at 22,860 meters, penetrating 441mm of side armour. At 18,288 meters, the penetration of the Mark 7 gun was 509 mm of side armour, so its performance is certainly on par with the Yamato's guns.
The SoDak and North Carolina classes mounted the 16"/45 Mark 6 gun, which fired the same 1225kg shell as the Mark 7. The striking velocity at 22,860 meters was 463 mps, with penetration of 382mm of side armour. At 18,288 meters the penetration is 448mm.
The British 16"/45 fired a 929kg round with a striking velocity of 453 mps second at 22,860 meters. Its armour penetration at this range was 261mm of side armour. At 18,288 meters, the penetration was 310mm.
As you can see, the Armour pentration on the British weapon is much lower than the american equivalents. The American Mark 6 weapon has superior pentration at 30,000 yards than the British weapon does at 20,000. This is why the British weapon does not get "Super AP." Clearly not all 16" weapons are created the same.
The 15"/42 used on the HMS Hood fired an 871kg projectile that had a striking velocity of 420 mps at 18,288 meters. The armour penetration at this range was about 279mm. Thus the Britich 16" shell is closer in performance to the British 15" shell than it is to the American's Heavy 16" shell. Thus the US battleships have Super AP and the british Nelson Class Ships are simply AP.
They did a good job with these rules. It may be that, out of fairness they give the brits a super AP ship. But doing this means that the Colorado Class and the Japanese Nagato Class also rate it. At that point the Hood has an argument for being super AP, and so does any ship with 15" guns. The British Queen Elizabeths would be Super AP, and the KGV would not.
I think the line is well drawn where it is. We don't want the Super AP classification to be meaningless.
Do you know how behave French and Italian 15" gun for this calculation ?
I have read that they are pretty much their shell weigh is pretty much on par with British 16" gun but their velocity are much higher because, being designed for the Mediterranean theater, they can accept to change their gun more often.
I have read that they are pretty much their shell weigh is pretty much on par with British 16" gun but their velocity are much higher because, being designed for the Mediterranean theater, they can accept to change their gun more often.
jbickley00
Mongoose
well the Italians did build very long range, very accurate guns. But the cost was a shorter barrel life, at least for the 15"/50 M1934 used on the Vittorio Venetto. Also the gun had a greater propensity for dispersion, so it was much less accurate at range.
This gun had shell weight of 885kg, and, at 20,000 meters had a striking speed of 563 meters per second. Penetration at 18,000 meter was 510mm, which elevates this gun into the super AP category. to be fair.
This is the longest ranged weapon put on a battleship-it could reach 44,640 meters at 36 degrees of elevation (the maximum allowed by the design. 9 more degrees of elevation would have only increased the range. in contrast the Yamato at 45 degrees (max elevation) had a max range of 42,030 meters.
The French used, on the Richelieu, a 15" (well 14.95")/45 that fired an 884kg shell that had a striking velocity of 544 mps at 20,000 meters with a penetration of 393mm of side armour at 22,000 meters.
the Dunquerque class used a 13"/50 that fired a 560kg round that had a striking velocity of 535 mps at 20,000 meters (this is a fairly high velocity shell) its side armour penetration was 342mm at 23,000 yards.
While respectable, the french guns were not quite super AP.
This gun had shell weight of 885kg, and, at 20,000 meters had a striking speed of 563 meters per second. Penetration at 18,000 meter was 510mm, which elevates this gun into the super AP category. to be fair.
This is the longest ranged weapon put on a battleship-it could reach 44,640 meters at 36 degrees of elevation (the maximum allowed by the design. 9 more degrees of elevation would have only increased the range. in contrast the Yamato at 45 degrees (max elevation) had a max range of 42,030 meters.
The French used, on the Richelieu, a 15" (well 14.95")/45 that fired an 884kg shell that had a striking velocity of 544 mps at 20,000 meters with a penetration of 393mm of side armour at 22,000 meters.
the Dunquerque class used a 13"/50 that fired a 560kg round that had a striking velocity of 535 mps at 20,000 meters (this is a fairly high velocity shell) its side armour penetration was 342mm at 23,000 yards.
While respectable, the french guns were not quite super AP.
Thank for the info.
I have compiled them in an array. It look like that this calculation said that the order of the Littorio and SoDak are misplaced in the penetration scale.
But of course this is just one factor amongst some other for a such simple representation as AP/AD
I have compiled them in an array. It look like that this calculation said that the order of the Littorio and SoDak are misplaced in the penetration scale.
But of course this is just one factor amongst some other for a such simple representation as AP/AD
Code:
Ship --- distance (km) Penetration ( mm of side armor )
---------------------------------------
Yamato : 20 494
---------------------------------------
Iowa : 18 509 22 441
---------------------------------------
Littorio : 18 510
---------------------------------------
Richelieu : 22 393
---------------------------------------
SoDak : 18 448 22 382
---------------------------------------
Dunquerque: 22 342
---------------------------------------
Nelson : 18 310 22 261
---------------------------------------
Hood : 18 279I am given to understand that the main cause for the inaccuracy of Italian guns was poor quality control in propellent charges, in gun callibres which used separate propellent and shells (i.e. 8" and over). The fact that all the shells in a salvo had varying amounts of propellent made for wide salvo spread, so whilst the italians nearly always straddled their opponents, they rarely caused hits.
I am unconvinced that the high muzzle velocity was a greater contributer to the innacuracy of italian naval gunnery than the propellant problem. look at the 6"and 5.3" gun. good italian crews performed sterling service in their light cruisers.
I would however like to mock my chosen navy and say that it was discovered that the DCTs weren't water proof, and so the gunsights malfuntioned in the rain
the italian navy is the only one in the world to have commissioned a report that i know of resulting in the observation that ships should be completely waterproof!
the allegation of italian guns being inacurate at long range is a little superfluous. NO ONES guns were accurate at long range
I think the longest ranged hit achieved on a moving target is something like 23,000 yards? and that was acknoledged pure luck.
for reference, I give you the quote of the Gunnery Officer on the HMS Warspite at Matapan, referring to the opening salvo at about 3500 yards:
"Good Lord, We've hit her!"
I am unconvinced that the high muzzle velocity was a greater contributer to the innacuracy of italian naval gunnery than the propellant problem. look at the 6"and 5.3" gun. good italian crews performed sterling service in their light cruisers.
I would however like to mock my chosen navy and say that it was discovered that the DCTs weren't water proof, and so the gunsights malfuntioned in the rain
the italian navy is the only one in the world to have commissioned a report that i know of resulting in the observation that ships should be completely waterproof!the allegation of italian guns being inacurate at long range is a little superfluous. NO ONES guns were accurate at long range
I think the longest ranged hit achieved on a moving target is something like 23,000 yards? and that was acknoledged pure luck.for reference, I give you the quote of the Gunnery Officer on the HMS Warspite at Matapan, referring to the opening salvo at about 3500 yards:
"Good Lord, We've hit her!"
jbickley00
Mongoose
Okay, so we here from the first Italian Fanboy. I like the Italians too, don't get me wrong, I think the Littorios should be Super AP, but they paid a price for thier velocity.
Yes, the italians did have quality control issues with thier powder charges, which led to accuracy problems. They also had quality control problems with the shells themselves. But, the guns also had a dispersion problem.
The Italian ships had a problem: they had a max gun elevation of 36 degrees. In the world of Naval Artillery (as opposed to say, super mortars) range is a factor of elevation-the greater the elevation the fartehr a shell will travel (up to a point- there is a sweetspot, somewhere aopund 45 or fifty degrees). The Italians were not wizards to abate the laws of physics, they simply increased the velocity of the gun, to get the extra range. They did this by increasing the powder charge to 490lbs (in contrast to the British 15" firing a 432lb charge). The increase in powder put an increase on the stresses to the barrel and thus barrel life was about half that of other nations guns.
The same stresses that shortened the barrel life, also impacted the guns dispersion-even small changes in the barrel produced dispersion problems at every range. Since battleships radar rely on consistency of fire to guide salvoes to the target, a gun prone to dispersion is problematic at any range. thus its not the high muzzle velocity that makes it inaccurate, its high barrel stress, and the suitability of the mountings and barrel to deal with the high recoil generated by the high muzzle velocity
The Italian 6" gun uncerwent two evolutions: 152mm/53 Models 1926 and 1929 used on the "Condottieri" Cruisers (except Garibaldi) had a very high muzzle velocity. In an effort to reduce the dispersion problem caused by inadequate construction, the muzzle velocity was reduced from 1000mps to 850mps. In addition the weight of the AP shells was reduced. When the Garibaldi class was created, the ships were equipped with a 152mm/55 model 34 (or 36) which had a lower muzzle velocity of 910 mps and better construction. These were also the secondaries on the Vittorio Venetto.
The 135mm/45 models 37 and 39 was a direct respons to the excessive muzzle velocity of the earlier 120mm/50 guns. The larger weapon gave the same range at a lower muzzle velocity, again to decrease dispersion, and thus increase accuracy.
It is fair to say the italians had a theoretical love affair with muzzel velocity, but in practice, they were reducing muzzle velocity to counteract dispersion problems. There were other factors in Italian Naval architecture that impacted dispersion on these ships too. But the Italian Navy went to great lengths to reduce muzzle velocity. You might be unconvinced that high muzzle velocity was a greater contributor to innacuracy than propelllant charges, but the italian navy was.
By long range, I don't mean the ultimate range of the weapon. I mean business long range-10'000 to 15-20,000 yards. Plenty of nations had accurate guns at these ranges. Or at least did not face the same dispersion problem.
The trouble with the Italian Navy was not the ships, the ships were world class, the trouble with the Italian navy is that its commanders lacked initiative, committment and aggression and it ships lacked radar.
Yes, the italians did have quality control issues with thier powder charges, which led to accuracy problems. They also had quality control problems with the shells themselves. But, the guns also had a dispersion problem.
The Italian ships had a problem: they had a max gun elevation of 36 degrees. In the world of Naval Artillery (as opposed to say, super mortars) range is a factor of elevation-the greater the elevation the fartehr a shell will travel (up to a point- there is a sweetspot, somewhere aopund 45 or fifty degrees). The Italians were not wizards to abate the laws of physics, they simply increased the velocity of the gun, to get the extra range. They did this by increasing the powder charge to 490lbs (in contrast to the British 15" firing a 432lb charge). The increase in powder put an increase on the stresses to the barrel and thus barrel life was about half that of other nations guns.
The same stresses that shortened the barrel life, also impacted the guns dispersion-even small changes in the barrel produced dispersion problems at every range. Since battleships radar rely on consistency of fire to guide salvoes to the target, a gun prone to dispersion is problematic at any range. thus its not the high muzzle velocity that makes it inaccurate, its high barrel stress, and the suitability of the mountings and barrel to deal with the high recoil generated by the high muzzle velocity
The Italian 6" gun uncerwent two evolutions: 152mm/53 Models 1926 and 1929 used on the "Condottieri" Cruisers (except Garibaldi) had a very high muzzle velocity. In an effort to reduce the dispersion problem caused by inadequate construction, the muzzle velocity was reduced from 1000mps to 850mps. In addition the weight of the AP shells was reduced. When the Garibaldi class was created, the ships were equipped with a 152mm/55 model 34 (or 36) which had a lower muzzle velocity of 910 mps and better construction. These were also the secondaries on the Vittorio Venetto.
The 135mm/45 models 37 and 39 was a direct respons to the excessive muzzle velocity of the earlier 120mm/50 guns. The larger weapon gave the same range at a lower muzzle velocity, again to decrease dispersion, and thus increase accuracy.
It is fair to say the italians had a theoretical love affair with muzzel velocity, but in practice, they were reducing muzzle velocity to counteract dispersion problems. There were other factors in Italian Naval architecture that impacted dispersion on these ships too. But the Italian Navy went to great lengths to reduce muzzle velocity. You might be unconvinced that high muzzle velocity was a greater contributor to innacuracy than propelllant charges, but the italian navy was.
By long range, I don't mean the ultimate range of the weapon. I mean business long range-10'000 to 15-20,000 yards. Plenty of nations had accurate guns at these ranges. Or at least did not face the same dispersion problem.
The trouble with the Italian Navy was not the ships, the ships were world class, the trouble with the Italian navy is that its commanders lacked initiative, committment and aggression and it ships lacked radar.
