What is ss deck gun ammo and what are the differences between the ammo types?

[Megatherion]

Hello everybody! I am brand new to Silent Hunter 3 and 4, and I was wondering what the ss ammo for the deck gun is. I figured out HE- high explosive, AP- armour piercing, AA- anti aircraft, and I think SS is sub sonic, but I am not sure. Also, what are the differences between the ammo types, ie what does each do? Any help with this would be greatly appreciated.

[smcj]

Greetings and welcome,

The SS "Star Shell" (flare on a parachute) is used to illuminate a target at night to aid you with your deck gun after you switch back to high explosives.

Good luck!

[Draka]

SS is StarShell.

Standard ammo types:
HE - High Explosive - blast damage, good against crew and soft targets, but doesn't make holes (penetrate)
AP - Armor Piercing - used against hard targets, but only puts holes in it - no boom-boom
AA - Anti-Aircraft - like it says - time-fused with a small blast charge (FLAK)
SS - Star Shell - illumination used to light up a target at night or other low light conditions

There is a debate on exactly what each Uboat actually carried - out of approx 220 rds of 105mm on U 199 there were 40 AA rds - see crew interrogation here: http://www.uboatarchive.net/U-199INT.htm

[Sailor Steve]

WELCOME ABOARD!

Looks like they've got you covered.

[RoaldLarsen]

Originally Posted by Draka

SS is StarShell.

Standard ammo types:
HE - High Explosive - blast damage, good against crew and soft targets, but doesn't make holes (penetrate)
AP - Armor Piercing - used against hard targets, but only puts holes in it - no boom-boom
AA - Anti-Aircraft - like it says - time-fused with a small blast charge (FLAK)
SS - Star Shell - illumination used to light up a target at night or other low light conditions

There is a debate on exactly what each Uboat actually carried - out of approx 220 rds of 105mm on U 199 there were 40 AA rds - see crew interrogation here: http://www.uboatarchive.net/U-199INT.htm

Those are the four type of ammo modelled in the game engine. GWX only provides HE for the deck gun. There are documented instances of U-boats using each of those four types of deck-gun ammunition in action, as well as two other types: semi-armour-piercing (SAP) and incendiary.

It is clear that the type and amount of deck gun ammunition carried on u-boats varied with date and circumstances (for instance AA ammunition seems to be more prevalent in 1943). I have not been able to find any clear references that show who was responsible for choosing which ammunition a u-boat carried. There is some indication that the u-boat's commander could at least influence the ammunication allocation.

HE ammunition could and did penetrate thin non-armoured plates, which is what almost all ships in the game (except battlehips and wooden vessels) are made of.

[Sailor Steve]

To add to the above, the so-called AP ammunition for shells this small was actually a Semi-Armor Piercing that would not penetrate the armor of even a light cruiser. The accepted standard was that this type of shell would penetrate approximately half of its own diameter, so a 4" shell could be expected to get through 2" of dedicated armor plate. Destroyers carried no armor, and the average merchant hull plating was less than 1/2" thick, so it was not really needed.

Of course the game reflects none of this.

While some boats were found to carry a variety of ammunition Campbell in his Naval Weapons of World War Two indicates that with the exception of the HE most other types were designated for surface ships. Carrying AA might be particularly useless simply because the deck guns could not elevate beyond 30 degrees. This would make them effective only against very low-flying aircraft.

[RoaldLarsen]

And the debate continues...

Campbell may indeed state this, but the proportion of primary source documents that indicate the use of non-HE ammunition by u-boat deck guns makes me question the value of his statement. HE was probably by far the most commonly used type of ammunition for u-boat deck guns, but it most certainly was not the only type of ammunition actually used by u-boat deck guns. I think that the historical record shows the use of multiple deck gun ammuntion types to have occurred so frequently that it is wrong to provide only one type of ammunition in the simulation.

For me it is an open question whether there was a SAP ammunition that was distinct from the AP ammunition. I have certainly seen reference to both, but I am not certain that I have seen reference to both in the same document. It is possible that both terms were applied to the same ammunition. However, I do have the impression that the AP was solid shot, while the SAP had a small base-fused explosive charge. I had understood that the distinction between the terms "AP" and "SAP" was design-based, not performance based. I can see little reason for the game to model these two types of ammunitions separately.

There is greater certainty that the incendiary was distinct from the HE. There are individual records indicating the use of both types of ammunition by a single gun in a single engagement. The damage model employed by the game would seem to give no reason for the game to model both types separately.

The lack of a high maximum gun elevation did limit the usefulness of AA deck gun ammunition, but remember that most aircraft tended to attack submarines from a low altitude. U-boats are known to have engaged aircraft with their deck gun using AA ammunition.

[Draka]

I simplified the designation quite a bit - I wanted the basics to be clear to the OP. As for HE vs AP, HE has an impact fuse and thus though it may cause a hole by the blast, it was not designed for such. AP was designed to make a hole as a primary purpose. This of course is very simplified - there are HE rounds with shaped charges, delayed fuze types of APC with secondary HE charges, etc - I really was trying to be basic and relate to in-game uses.

[Sailor Steve]

Originally Posted by RoaldLarsen

And the debate continues...

I didn't mean to start it up again. My intention in referencing Campbell was to show where the GWX changing of everything to HE came from. In fact Campbell's wording is vague, but at the time I originally brought it up it was what I had. When I read the later capture reports I was surprised, but not overly so. It's obvious that the captain had some leeway in the loadout he carried.

For me it is an open question whether there was a SAP ammunition that was distinct from the AP ammunition. I have certainly seen reference to both, but I am not certain that I have seen reference to both in the same document. It is possible that both terms were applied to the same ammunition. However, I do have the impression that the AP was solid shot, while the SAP had a small base-fused explosive charge.

That I do know a bit more about, from my experience with years of research for my own naval tabletop miniatures game.

When the British commissioned the Majestic class battleships in 1893, the loadout cosisted of "Armour-piercing solid shot, Armour-piercing shell, Semi-armour-piercing common, and dummy rounds", with no High explosive. The problem at that time was that no one was sure that an AP shell would even work. By the First World War the AP solid shot was gone, the loadout was mostly AP shell, along with some Common and HE. Common was for use against unarmored targets and HE was meant for shore bombardment.

Destroyer guns of the period had Common rounds and nothing else, and carried the wonderfully awkward designation of SAPCBC (Semi-Armour-Piercing Capped British Common).

In World War Two the famous US dual-purpose 5"/38 carried no HE, but a Common type called HC, for High-Capacity, which was designed to pierce the roof of a small concrete bunker, along with AA rounds, which was why they were 'dual-purpose'.

My copies are all in storage, so I can't give you specific issue numbers, but most of this comes from various issues of Conway's Warship magazine and the Amercan Warship International, including articles on the Majestic class battleships and HMS Bulwark, of the London class. They also contain Campbell's series 'British Naval Guns: 1880-1945.'

Another source I love is also by Campbell: Jutland - An Analysis Of The Fighting. It contains a shot-by-shot description of the battle - who fired what type of shell, where it hit and damage done. The best part is the information that one British battleship (I think it was Hercules) was loaded for a bombardment mission and went into the battle with nothing but HE!

I had understood that the distinction between the terms "AP" and "SAP" was design-based, not performance based. I can see little reason for the game to model these two types of ammunitions separately.

As I said, there is a big difference but I'm pretty sure that nobody ever made a true AP round for any gun smaller than 6", so your judgement stands. M. J. Whitley, in his book German Destroyers of World War Two, says that the actual German terms stood for 'Nose-fused HE' and 'Base-Fused HE', so I don't know if the German 'AP' (or 'SAP') round was actually capped at all, but rather was just an HE round with a base-mounted fuse to delay the explosion to guarantee full penetration of an unarmored hull before going off.

There is greater certainty that the incendiary was distinct from the HE. There are individual records indicating the use of both types of ammunition by a single gun in a single engagement. The damage model employed by the game would seem to give no reason for the game to model both types separately.

Probably true, but I'm not familiar with how the game models work so I'm not in a position to argue one way or the other.

The lack of a high maximum gun elevation did limit the usefulness of AA deck gun ammunition, but remember that most aircraft tended to attack submarines from a low altitude. U-boats are known to have engaged aircraft with their deck gun using AA ammunition.

Also true. The only story I heard of a u-boat shooting down a plane using its deck gun didn't say whether they even used an AA round. Pretty funny if they did it with a standard round!