Retrofit German ACRs to counter RN 1st gen battlecruisers

The Germans were tricked into making the 8.3" armed Blucher armoured cruiser when they should have been making Nassau to counter the British Invincible class battlecruisers.

Could the German navy's five most modern armoured cruisers (Blucher, Scharnhorst-class, Roon-class), have been updated to stand in battle against Invincible and the RN's other 12" armed battlecruisers? Tearing them down and changing to turbines or more powerful machinery is not likely an option due to the time and expense - might as well focus on building more Nassau class.

So, to start with, we'd need to increase their firepower. Per http://www.navweaps.com/ Blucher's 21 cm/45 (8.27") and the four earlier 21 cm/40 (8.27") guns fired a 238 lb projectile, vs. the Invincible's 12"/45 firing 850 lb projectiles. Can we replace the 8.27" guns with fewer of the 9.45" gun (474 lb projectile) from Austria, http://www.navweaps.com/Weapons/WNAust_945-45.htm

The complete twin gun Austrian turret weighed 235 tons, vs. Blucher's twin gun 8.27" turret at 197 tons. The twins on the Roon and Scharnhorst class weighted 171 tons.

Roon-class

Roon_linedrawing.png


Scharnhorst-class

Scharnhorst_class_Brassey%27s.jpg


Blucher

SMS_Blucher_line-drawing.png


As a comparison, here is the earlier Austrian 9.4" gun in the KuK cruiser Erzherzog Ferdinand.

640px-Erzherzog-class.JPG


640px-Smserzherzogfriedrich.jpg
 
My thinking is if Scharnhorst and Gneisenau have these heavier guns they may penetrate and blow up the BCs at the Falklands. The Germans had to have known battlecruisers would be sent against them after Coronel.
 
Do they need bigger guns to penetrate 4-6" armour? Wouldn't giving the guns more elevation and upgrading the fire control so they could match the engagement range of the early RN BCs take some of the sting away?
 
My thinking is if Scharnhorst and Gneisenau have these heavier guns they may penetrate and blow up the BCs at the Falklands. The Germans had to have known battlecruisers would be sent against them after Coronel.

RN Battlecruisers weren't using suicidal magazine practices at that time so there is less risk of that happening but heavier German guns should mean more damage per hit but a slower rate of fire.
 

GarethC

Donor
My thinking is if Scharnhorst and Gneisenau have these heavier guns they may penetrate and blow up the BCs at the Falklands. The Germans had to have known battlecruisers would be sent against them after Coronel.
The BC losses at Jutland came from turret hits which flashed into the magazines, IIRC. NavWeaps gives the penetration of the 9.4" as 6.7", which is shy of the 7" protection on the I-class turrets. Also, pre-Dogger Bank, the RN BCs had a more sensible approach to not-blowing-up cordite storage.

Invincible
did take a diving shell into a coal bunker adjacent to a magazine at the Falklands, but it was insufficient to penetrate. It's not clear that the 9.4" would have the same diving characteristics or be sufficient to penetrate to the magazine either.
 
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Basically the Invincibles and Indefatigable classes were just other armroed cruisers, with the same scale of protection as other armored cruisers, coubled with larger dimensions and turbines, besides bigger main guns. The type was called armored cruiser until the stat of the war itself, or sometimes labeled as "Dreadnought Cruisrs", indicating it was a logical development of the large armored cruiser type, which wa primarily seen as a ocean going Multi role ship for either trade protection, or commerce raiding in wartime, while the smaller scout type light cruiser was more a fleet unit to operate with the battlefleet. The idea to put armored cruisers in a battlefleet was first executed by the Japanese as Tsushima, where the wing of armored cruisers had a devastating effect on the Russian 2nd Pacific Squadron. The Fisher called Dreadnought Cruisers were supposed to fulfill in such a role as well, while the older Armored cruisers were actually never thought to do this sort of missions.

In any case, the German 8.2 inch gun was quite capable in itsefl, though shorter ranged compared to the 12 inch gun on the early British Battlecruisers, so the Invincible and Indefatigable classes had some advantage over their 8.2 inc gunned last gerneration German Armored Cruisers, prior to SMS Von Der Tann. The 8.2 inch gun could penetrate all armor of the 1st generaion British Battlecruisers, but only under ideal conditions. More likely was the sort of Flashdamage and destruction seen at Juttland, where the turrets and ammunitions, combined with procedures were the most elementary flaw in the quick destruction of the British ships. Even at the Falklands, the German 8.2 inch guns could have done a simmilar thing, were it not Sturdee did wise to stay at long range, of the two armored cruisers of Von Spee, limmiting the chnge of fatal damage to his ships.
 
Are there other guns that could be considered? Perhaps a "light" weight 10 or 11"?
No, the problem you have is that, without a reconstruction almost expensive as buying a new ship (possibly more expensive), is that you are limited in the size of the turret by the size of the Barbette. Even in your first suggestion, I think the barbette needed for the twin 24cm, is bigger than the twin 21 cm on either ACR. I suppose you could switch out twin 21cm for single 28cm guns, but that wouldn't really be useful enough, too few barrels
 
Hmmm..... can we retrofit the 8.27" gun to fire a projectile larger or at much higher MV than its 238 lbs? Something like a super charged shot?

The best known cruiser-sized, battlecruiser-killing gun is the 20.3 cm/60 (8") of WW2's Admiral Hippers. These guns, while smaller in diameter than 8.27" fired a 269 lb projectile.
 

NoMommsen

Donor
Hmmm..... can we retrofit the 8.27" gun to fire a projectile larger or at much higher MV than its 238 lbs? Something like a super charged shot?

The best known cruiser-sized, battlecruiser-killing gun is the 20.3 cm/60 (8") of WW2's Admiral Hippers. These guns, while smaller in diameter than 8.27" fired a 269 lb projectile.
What IS possible in this calibre size might be shown by the super heavy 8" shells of USN in WW2 (335 lbs, even more than the last german WW1 9.4" guns with 308.6 lbs).
If Krupp were given the task to develop such a shell some/a few years before WW1 started, I would be confident, that they could develop such a shell in the 300 + lbs range for this gun. (But as the noob I am on such shell-against-armor-stuff I have no idea, if this could/would considerable improve i.e. Scheers possibilies against the british BCs at Falkland.)
But ...
the range might be decreased. To counter that you would also need to develop a new charge (more densly packed ?, longer burning powder ?)... and - perhaps - a modification of the gun chamber and breech. That might be more easily done with Blüchers guns. If the Roons and Scharnhorts' turrets had enough space to accomodate such a gun (45 caliber length as Blüchers, interestingly these longer-barrel guns were even lighter than the ones build into the former ACs) I have no idea.
 
They had a longer shell for the 11" gun by the time Seydlitz was ordered, but it was found that this shell would have required extensive reworks in the turret layout and was therefore not used. I doubt it would be different for the 8.3" turrets.
 
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