Suggestion for more "REALISTIC" gun penetration

[Alexandre Nozzang]

Before starting to the topic, I would like to say that this game is my pleasure as an engineer and a military hip.

As I am playing this game, I came to realize that the penetration of the shells are quite awkward. In other word, unrealistic.

 

According to the Krupp's penetration formula, the penetrating distance is like this:

2.9*[{(E^3)/(D^5)}^0.25]*v^-0.25

where E is the kinetic energy of projectile, D is a diameter of shell in mm, v is a velocity. The result is shown in mm.

 

Under that formula, BB Iowa's 16" gun can penetrate 784 mm, or 30.9".

It is quite apart from the historic 32.62" penetration result but it can be mitigated via manipulating some armor coefficients.

 

As an engineer, I had also figured out with a penetration formula by adapting fluid dynamics long ago.

 

The formula is shown as this:

m/(2*rho*A)*ln((rho*v^2)/(2*Y))

where

m: mass of a projectile

rho: density of armor

A: area of projectile

v: velocity of projectile

Y: compressive strength of armor

the result is in metric. ln() is a natural logarithm

 

By putting rho and Y of Cu-Ni steel alloy(7250 kg/m^3, 582.6 MPa), we get the result of 0.828 m or 33". Which is quite similar to historical data.

The Y, or compressive strength can be modified as a armor coefficient of in-game armor type, so I deem that this formula would be much more adaptable.

 

 

 

 

The reason why I am showing these formula is that the penetration of 20" guns are extraordinarily high.

Lets talk about in-game H-TNT 20" SHS.

Its gun report shows that it could penetrate 74.3" of side armor at dist 1000 m.

However, according to the formula I had shown above, they show that it could penetrate 38.3" and 39.8" each at point-blank. Which is very apart from the game.

 

I do understand that the historic data of 20" guns are in mystery, but it can be expected through mathematical analysis. Although some may argue that the formula I had shown above does not have any citations, but no matter what, this is just my suggestion hopping UAD to do some management for unknown unrealism.

Edited March 9, 2021 by Alexandre Nozzang

[Bigjku]

Agree that the large guns are way overpowered.  There are diminishing returns as shells get bigger.  The game doesn’t seem to reflect that.

[Cpt.Hissy]

25 minutes ago, Bigjku said:

Agree that the large guns are way overpowered.  There are diminishing returns as shells get bigger.  The game doesn’t seem to reflect that.

Why diminishing results may i ask? (this would be quicker than extensive hit-and-miss googling required to find relevant data)

[Bigjku]

Simple math starts the equation really.  Going from 12 to 14 is a bigger change than going from 14 to 16 and 16 to 18 is smaller yet again.

For the USN you see this progression of shell weights for the relatively contemporary 1910’s guns.

12 inch:  870 pounds

14 inch: 1,402 pounds (61% heavier) Gun Weight 90 tons

16 inch:  2,110 pounds (50% heavier) Gun Weight 118 tons (31% heavier)

18 inch:  2,900 pounds (37% heavier) Gun Weight 180 tons ( 52% heavier)
 

Now the gun weights are debatable as I used the 14/50, the 16/45 and the 18/48.  They aren’t a like for like caliber match.  But those are the guns they built that the clearly felt were optimal for what they could achieve for battleships. Keep in mind that gun and shell weight have all sorts of knock on effects that add weight.  All the gear to elevate the guns gets heavier.  All the shell handling gear gets heavier and stronger.  All the spaces to physically house the gun, it’s driving gear, the shells and the bigger powder chargers gets bigger requiring more volume to be armored.

A turret for Yamato was 2,774 tons.  The turret on a North Carolina was roughly half that at at 1,384 tons.  Those guns were roughly the same caliber 45/46.  For all that weight you got a 3,218 pound shell vs a 2,709 pound shell so 19% heavier.  You get for this about 2-4 more inches of penetration at 20,000 yards depending on what numbers you trust but the 16 inch should still go through 17 inches plus of armor which was enough to get through most all things.

Weight just starts to add up real quick as you go to huge guns.  I can even imagine what a realistic 20 inch installed turret would look like honestly Japan looked at it for the Yamato successor and on 80,000 tons said we can maybe do 6 guns in 3 twins of that size.  Seeing as it wasn’t built I suspect if anything this was optimistic on their part.

[madham82]

6 hours ago, Alexandre Nozzang said:

The reason why I am showing these formula is that the penetration of 20" guns are extraordinarily high.

Lets talk about in-game H-TNT 20" SHS.

Its gun report shows that it could penetrate 74.3" of side armor at dist 1000 m.

However, according to the formula I had shown above, they show that it could penetrate 38.3" and 39.8" each at point-blank. Which is very apart from the game.

The in-game tables are not based on steel but iron it appears. So read their values from that context as all guns are impacted not just the 20" (for example the mk3 16" has a side pen value of 53" at 1000m). Also we have learned the deck pen values are essentially useless since they do not take into account shell fall angle.

[o Barão]

8 hours ago, Bigjku said:

Agree that the large guns are way overpowered.  There are diminishing returns as shells get bigger.  The game doesn’t seem to reflect that.

Strange. For me is the opposite. Usually i will not go with guns bigger than 16 inch shells. The reload penalty/gun weight/gun size is just too much imo. 

[Bigjku]

8 minutes ago, o Barão said:

Strange. For me is the opposite. Usually i will not go with guns bigger than 16 inch shells. The reload penalty/gun weight/gun size is just too much imo. 

I won’t either as I am a stickler for trying to have realistic ships.  But I have run up against AI designs on the biggest of ships that sport 9 or more 18 inch or bigger guns and the semi or auto loading perk.

[o Barão]

27 minutes ago, Bigjku said:

I won’t either as I am a stickler for trying to have realistic ships.  But I have run up against AI designs on the biggest of ships that sport 9 or more 18 inch or bigger guns and the semi or auto loading perk.

I don't use 16 inch guns because they are realistic. And I don't have any problems in seeing AI using 18 inch or 20 inch guns. If it is possible for them to use why not? The British already had 18 inch guns in WWI. Now there are penalties for using them and imo is not worth it. Rate of fire/ accuracy and enough pen are what i value the most.

[Draco]

We've actually just gone over this with nick and the team in a separate thread. I have just gotten confirmation that they will take another look at gun penetration values in the next hotfix.

[Stormnet]

On 3/9/2021 at 9:42 PM, o Barão said:

Strange. For me is the opposite. Usually i will not go with guns bigger than 16 inch shells. The reload penalty/gun weight/gun size is just too much imo. 

There are people that go for the biggest guns possible to deal massive damage.

There are people that go for lighter guns possible to maintain decent firerate. 

While I am sitting here wondering why am I trying to do both:

Quad 50 inch in the front, 3 quad 15 inch around the ship.