Best Battlecruiser WW1 and WW2

From the Washington Naval Treaty to the end of the Second World War.
alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Best Battlecruiser WW1 and WW2

Post by alecsandros »

VoidSamukai wrote:Really? I thought that the Iowas and SDs were protected against 16inch caliber shells.
... They were, but not against the new type 2700pds 16", but the old type 2240lbs 16" round.

The German 1760" 15" round had more penetration at usual combat ranges than the old 2240 16" round, mainly because of it's higher initial velocity.
User avatar
VoidSamukai
Member
Posts: 77
Joined: Thu Nov 05, 2015 11:42 pm

Re: Best Battlecruiser WW1 and WW2

Post by VoidSamukai »

I still wouldn't place my money on a Scharnhorst against a SD. Even though they "could" penetrate each other, SD has more guns which means more firepower can be brought to bear on the enemy.
alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Best Battlecruiser WW1 and WW2

Post by alecsandros »

VoidSamukai wrote:I still wouldn't place my money on a Scharnhorst against a SD. Even though they "could" penetrate each other, SD has more guns which means more firepower can be brought to bear on the enemy.
I wouldn't either.
User avatar
Dave Saxton
Supporter
Posts: 3148
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Best Battlecruiser WW1 and WW2

Post by Dave Saxton »

alecsandros wrote:
The German 1760" 15" round had more penetration at usual combat ranges than the old 2240 16" round, mainly because of it's higher initial velocity.
At usual combat ranges, not only did it have more penetration than 2240lb, but it had more penetration than the 16"/45 with the 2700lb, and essentially the same penetration as the 16"/50 with the 2700lb. This is because velocity is more important than weight among similar caliber shells when it comes to face hardened armour penetration. (also shell head shape is more important than weight as well).

The Rodney 16" had essentially the same belt penetration as the Iowa 16"/50 and the German 15"/52 at 20,000 yards.

The Iowa/SD IZ was from 21,000 yards to 31,000 yards vs the 2240 lb shell*, but the designers didn't count on the American face hardened armour coming in at such poor quality.
Even though they "could" penetrate each other
On the other side of the ledger the 16" guns can not defeat the Scharnhorst's scarp triangle belt protection system.

*the deck penetration of the 16"/45 with 2240 lb shell and the 16"/50 with 2700 lb shell is essentially the same and Iowa's deck protection was 140mm effective.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Best Battlecruiser WW1 and WW2

Post by alecsandros »

... Still US 16"/L50 retained more perforating power beyond 20km than the German 15"/L52. That is were the US gun truly shines.

... Scharnhorst's scarp triangle was very strong , as was Bismarck's. But, 6 smaller guns versus 9 bigger guns is almost always a losing statement.

Best,
User avatar
Dave Saxton
Supporter
Posts: 3148
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Best Battlecruiser WW1 and WW2

Post by Dave Saxton »

alecsandros wrote:... Still US 16"/L50 retained more perforating power beyond 20km than the German 15"/L52. That is were the US gun truly shines.

...
Best,
The difference is less than 3/4 of an inch all the way out to 30,000 yards.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Best Battlecruiser WW1 and WW2

Post by alecsandros »

Dave Saxton wrote:
alecsandros wrote:... Still US 16"/L50 retained more perforating power beyond 20km than the German 15"/L52. That is were the US gun truly shines.

...
Best,
The difference is less than 3/4 of an inch all the way out to 30,000 yards.
I don't know if it's only that small.
The larger shell has the advantage in punching through armor plate, as it has a bigger pushing mass. It also retains a larger velocity than the smaller shell, per unit of range traveled.

At 25000 meters, a range at which Tirpitz did gun trials, the 380mm L52 is credited with 335mm of German KC n/A perforated, as in GKDOS100.
At same range, Iowa's guns could still perforate some 360mm of British Cemented Armor new type.

It's always a hussle to compare to different armor plates from different manufacturers, not to mention countries and different historical periods... But all in all, the 16"/L50 was more powerfull than the 15"/L52, and , very imporantly, delivered a much larger shell to the target.
Steve-M
Member
Posts: 53
Joined: Wed Dec 30, 2015 6:38 pm

Re: Best Battlecruiser WW1 and WW2

Post by Steve-M »

Dave Saxton wrote:The Rodney 16" had essentially the same belt penetration as the Iowa 16"/50 and the German 15"/52 at 20,000 yards....On the other side of the ledger the 16" guns can not defeat the Scharnhorst's scarp triangle belt protection system.
FWIW, doing a little crunching with Naab yields these figures:

Belt / Deck Iowa SoDak Nelson Bismarck
15k yards 22.0/3.3 19.4/3.4 19.3/2.8 19.6/2.5
20k yards 19.1/3.9 16.8/4.0 16.2/3.3 16.5/3.1
25k yards 16.9/4.5 14.7/5.0 13.9/4.1 14.2/3.6

Numbers are derived from specifying complete penetrations into 12" worth of German improved thick-plate KC n/A backed by 1" of mild steel for vertical plating, and 5" of Wotan Weich for horizontal plating. For the US figures, I used the 16" Mk8 Mod 6-8 APC, with an MV of 2500fps and 2300fps for Iowa and SoDak respectively. With the above, the US 16/L45 appears fairly comparable with the weapons aboard Bismarck and Nelson, with Iowa's 16/L50 representing an incremental improvement in vertical armor penetration.

In terms of "tearing ships apart"...certainly all of the above will do that at any realistic battle range. As resilient as the German scarp/belt system is, Scharnhorst as a whole is quite vulnerable to these weapons.
User avatar
Dave Saxton
Supporter
Posts: 3148
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Best Battlecruiser WW1 and WW2

Post by Dave Saxton »

alecsandros wrote:
I don't know if it's only that small.
The larger shell has the advantage in punching through armor plate, as it has a bigger pushing mass. It also retains a larger velocity than the smaller shell, per unit of range traveled.

At 25000 meters, a range at which Tirpitz did gun trials, the 380mm L52 is credited with 335mm of German KC n/A perforated, as in GKDOS100.
At same range, Iowa's guns could still perforate some 360mm of British Cemented Armor new type.

It's always a hussle to compare to different armor plates from different manufacturers,et.

I'm using Nathan's face hard model data against British CA.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Best Battlecruiser WW1 and WW2

Post by alecsandros »

@Steve-M

NaaB is an interesting tool ,

research in the latest years however showed it to be downgrading real Krupp post-1935 armor plate by about 5 to 10%.
In other words, German armor at least is stronger than what NaaB predicts.

German trials with the 380mm gun against German armor produced the following results:
20000yards= 17.5"
25000yards= 14.25"
30000yards= 12.05"
Steve-M
Member
Posts: 53
Joined: Wed Dec 30, 2015 6:38 pm

Re: Best Battlecruiser WW1 and WW2

Post by Steve-M »

alecsandros wrote:NaaB is an interesting tool , research in the latest years however showed it to be downgrading real Krupp post-1935 armor plate by about 5 to 10%.
In other words, German armor at least is stronger than what NaaB predicts.

German trials with the 380mm gun against German armor produced the following results:
20000yards= 17.5"
25000yards= 14.25"
30000yards= 12.05"
Not really a big issue for the practical implications of my post. Even if you substitute the aforementioned vertical plating with 12" of British post 1930 NCA backed by 2" of Ducol steel, NaaB reckons the 16/L50 will achieve a complete penetration through 15.6" of plating at 25,000 yards, with the 16/L45 not too far behind at 13.5". The implications ultimately remain the same: regardless of how immune the scarp/belt region is, Scharnhorst as a whole is very vulnerable at any expected battle range.
User avatar
Dave Saxton
Supporter
Posts: 3148
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Best Battlecruiser WW1 and WW2

Post by Dave Saxton »

Let us not forget that an Iowa/SD is also very vulnerable to the German 15" at any battle range.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
Steve-M
Member
Posts: 53
Joined: Wed Dec 30, 2015 6:38 pm

Re: Best Battlecruiser WW1 and WW2

Post by Steve-M »

Dave Saxton wrote:Let us not forget that an Iowa/SD is also very vulnerable to the German 15" at any battle range.
As I said, any of those weapons are quite effective at ripping ships apart. Still, with 9 barrels to 6, and ~2660lbs vs ~1720lbs worth of steel being accelerated by ~40lbs of high explosives in the case of a penetrating hit, it wouldn't be a wise fight for a German commander to pick.
User avatar
RF
Senior Member
Posts: 7759
Joined: Wed Sep 20, 2006 1:15 pm
Location: Wolverhampton, ENGLAND

Re: Best Battlecruiser WW1 and WW2

Post by RF »

Don't forget that the twins generally operated as a pair.

12 guns rather than six, mounted on two different firing positions - would you agree that would change the odds?
''Give me a Ping and one Ping only'' - Sean Connery.
Steve-M
Member
Posts: 53
Joined: Wed Dec 30, 2015 6:38 pm

Re: Best Battlecruiser WW1 and WW2

Post by Steve-M »

RF wrote:Don't forget that the twins generally operated as a pair.

12 guns rather than six, mounted on two different firing positions - would you agree that would change the odds?
Undoubtedly. Of course, if the American battleship is supported by a task force as they tended to be, the twins would likely be sunk before they got within 100 miles of Iowa or SoDak :D
Post Reply