Christian VII. wrote: alecsandros wrote:
Christian VII. wrote:I don't know if I find it odd that a 28 cm gun could out penetrate a 35 cm gun, esp. when the muzzle velocities are considered. The 28cm C/34's did after all fire their projectiles ~120 m/s faster, which would also help reduce the impact angle vs vertical belt armour.
You can't find it odd, because it is wrong.
At 20km the 283mm gun coudl perforate about 280mm of vertical KC armor. At same range the 356mm gun could perforate about 360mm of British cemented armor.
I don't know, thus I think I can find it odd that one form of calculation, the USN one, has the 280mm C/34 outperform the 356mm Mark VII, can I not?
I don't know how KC armour compared with British cemented armour either, and wether one gun was better against one type of armour than the other. It depends on the shape and composition of the respective penetrators, as well as the size & composition of the target plate.
But at least in terms of raw energy concentration the 280mm C/34 actually holds a slight edge initially.
Nathan Okun modeled both guns, you probably know the results.
In his own words, his model comes withing 13% of British field tests and within 10% of American field tests.
Most contemporary research that I know of puts British CA and Krupp KC n/A at rough parity in terms of stoping power of BB caliber shells.
The 356mm/L45 projectile is simply much to powerfull to compare it to the German 283/L55 projectile.
Modeling shows a difference of ~ 50% in penetration of same type of plate (either both German or both British) at 20km.
Even allowing tolerances of up to 10-15%, which can account for different metodologies of testing between countries, different properties between plates, different proprieterties between projectiles, the 356mm is head and shoulders above
the 283mm gun.
The 283mm gun has a higher initial velocity than the 356mm gun, that's why it has that initial energy.