Deckgun - Bow vs Stern

[DeePsix501]

Howdy all,

My friend and I were discussing the difference between the subs of SH3 and SH4. We eventualy talked about deckguns, and pointed out that germans mounted it on the bow of their subs and we did too with our early S class subs. Why over the course of the war did the Germans keep the guns on the bow and the United States keep the guns aft of the conning tower? Was there some theoretical doctrine to why the gun should be mounted aft?

Just wondering :ping:

[Hyena]

Maybe for the same reason the Germans removed their deck guns? IE Hydrodynamics.

I would think something mounted aft of the tower would be in it's slipstream, and cause less drag in the water.

Of course I could be wrong and it's something totally different.

[Skweetis]

THat seems a logical explanation Hyena. I'd agree with that.

[Takao]

The US didn't keep the deck gun aft of the sail. Placement of the deck gun was left to the captain of the submarine. Unlike the German U-Boats, US submarines(from the P-Class on) were fitted with two hard points for deck guns. One was forward of the sail, and one aft of the sail. This is why you are allowed to select placement of the deck gun either fore or aft.

[StandingCow]

Pretty nice having it aft when ya get a destroyer on your tail (too easy to take them out with the deckgun).

[DeePsix501]

Oh I understand that we were given the choice of putting forward or aft, but why did most commanders put it aft? I'd agree with the hydrodynamics aspect.

[panthercules]

Maybe for the same reason the Germans removed their deck guns? IE Hydrodynamics.

I would think something mounted aft of the tower would be in it's slipstream, and cause less drag in the water.

Of course I could be wrong and it's something totally different.

I could be wrong, but I believe that the Germans removed their deck guns more because they had become essentially useless (because of the increased danger/futility of trying to take on armed merchants with air cover through surface gun battles as the war progressed) than for reasons of hydrodynamics.

I'm not sure exactly what the American reasoning might have been, but if it had been up to me I would have put the deck gun aft of the tower for a couple of reasons - (1) I would think that the tower would provide something of a breakwater effect that would allow a deck gun behind the tower to be safely manned in at least somewhat heavier seas than if it were located in front of the tower and therefore more exposed to the seas crashing over the bow, and (2) I would rather be able to engage the enemy ships with my gun while pointing away from them (and thus be ready to high-tail it out of there if they started firing back or chasing me) rather than only while pointing toward them (making it much harder to turn around and get out of there if necessary).

[WFGood]

"The thinking was that a deck gun was most needed when a boat was running for deep water and a gun mounted forward of the conning tower could not be trained aft!" That was taken from a submarine veteran's website.

Here is another quote from valoratsea.com:

Initially, deck guns were considered by many to be an extraneous and dangerous piece of hardware for submarines at the beginning of the war. Principally, the reasoning was that a submarine is basically a poor platform for a deck gun. Owing to the fact that the vast majority of the sub fleet's war patrols within 500 miles of Japanese bases were conducted submerged, the value of the deck gun was severely questioned. Additionally, it was reasoned that a submarine in a head to head gun battle with an enemy in possession of equal (or greater) firepower was at serious risk. Any enemy hits on the submarine which could impede or prevent her ability to submerge was justification enough to avoid a surface gun action. That's not to say that submariners didn't take advantage of some welcomed target practice when the opportunity arose. US Submarines that were scouting the Japanese Empire waters frequently came upon sampans, which were often suspected of being naval lookouts or anti-submarine pickets. By April of 1942, submarine skippers decided to start thinning out the sampan fleet and a periscope contact often resulted in the order of "Battle Surface". The results of a piboat going up against a lightly armed, floating bundle of wood one would think could be easily determined, however sinking these pesky little vessels was not a simple as first thought. Theodore Roscoe, in his book US SUBMARINE OPERATIONS IN WW II, states: "They could be riddled with .30 and .50 caliber machine gun bullets and holed several times by 3 or 5 inch shells and remain afloat like a box of Swiss cheese". More often than not, a submarine's deck gun was of greater value for overall morale than it was for combat effectiveness. A submerged boat that was damaged by an enemy surface vessel could, as a last ditch effort to survive, surface and engage in a gun battle, although with the odds generally stacked heavily against it. The deck gun was the ultimate weapon of last resort and it has been suggested that the 3, 4 or 5 inch guns (used for both anti-aircraft and surface actions and typically located abaft of the the conning tower), was therefore justified.

[Hitman]

I recall having read in O'Kane's "Clear the Bridge" how much he had to discuss with the bureau of material to be allowed to change his deck gun from aft to fore. Apparently, the reasoning behind the stock design of mounting deck guns aft in fleet boats was that they were for defensive purposes, when the boat was unable to dive and had to escape. That way they could shoot at the pursuer while running in the opposite direction.

But O'Kane wanted just the opposite: To be able to chase smaller and faster vessels -not worth a torpedo- while shooting at them.

In german U-boots, deck guns were mounted to finish off crippled targets or taking on smaller vessels not worth a torpedo, and for that offensive purpose they were mounted normally forward. As war progressed and the merchants were equipped with guns, and aircraft represented a real threat, guns were abandoned in benefit of higher underwater speed and less noise (turbulences from a submerged deck gun are noisy).

[Assertor]

bow bow bow bow!

[Nokia]

I have the gun mounted aft so i can defend myself when trying to get away from destroyers when i'm on the surface...

[WFGood]

Those quotes that I had posted earlier seem to sum it up. At first they were thought to be useless, until they realized that a damaged submarine trying to escape or at least trying to make to deep water in order to be able to submerge would be better served by being able to fire at a pursuing escort. People like "Mush" Morton and Dick O'Kane would probably have wanted them forward in order to hunt. I personally like mine in the stern, but it does make it difficult to chase down a surface vessel and sink it that way.

[Ducimus]

Those quotes that I had posted earlier seem to sum it up. At first they were thought to be useless, until they realized that a damaged submarine trying to escape or at least trying to make to deep water in order to be able to submerge would be better served by being able to fire at a pursuing escort. People like "Mush" Morton and Dick O'Kane would probably have wanted them forward in order to hunt. I personally like mine in the stern, but it does make it difficult to chase down a surface vessel and sink it that way.

LOL, yup, guess where he put it:
http://en.wikipedia.org/wiki/Image:USS_Wahoo_SS-238.jpg

[danoh]

I was tempted to move the deckgun forward to what I was used to in SH3, and because I tend to use it offensively and not running away, but I've stuck with the aft mount and it makes for some different sailing decisions.

I do notice the deck guns are accurate at longer ranges, but alternatively will miss a lot when you are inside 500 yards. The optimal range seems to be between 1000-2000 yards when I'm having the crew fire it.

And you can also man it in much heavier seas now.

[Meco]

Since there are 2 hardpoints, did they ever mount 2 deck guns? Fore and Aft?

That would be a neat feature in SH4. (goto deck gun) command could cycle. once for fore, and a second time for aft.

hmmm. :hmm:

[NEON DEON]

Oh heck just bribe the supply officer and mount 2 of em!:D

No need to have to decide;)

[Doomgiver]

heck that would be fun, but on the sub upgrade screen why is there two different deck guns for both the bow and stern

[AntEater]

There is a deck gun modification with 2 5 inchers, but it is hard to spot, as it is not named "2 guns".
It costs 2000 renown, thats how you can spot it.
You can only man one of them, though, but two are actually shooting.
But since you're upside down on the five incher, who wants to man it anyway??
Btw, the five incher was a unique weapon, some kind of sawn-off destroyer gun with a much shorter barrel.
Some earlier boats in Freemantle had guns from the old V class boats, which were regular (longer and heavier) five inchers.

[DeePsix501]

I wish the game would give us little paragraphs about the weapons/upgrades we put on our sub, so I could know a little more about it...

[-Pv-]

"...I wish the game would give us little paragraphs about the weapons/upgrades we put on our sub, so I could know a little more about it..."

What, and not have to take advantage of the wealth of sub lore on this website?
You can get more WWII hsitory reading 5 pages in this forum than most of us get all our lives.

On the other hand, I got more ignorance from reading 5 pages of rants than I got in 30 years at the workplace.

Balances out. I'm both smarter and dumber. Depends on whom I believe.

Right now I'm in favor of the front mount as I only intend to use it to attack.

The one time I had it as a rear mount being chased by a DD it chewed me up pretty badly and I only inflicted minor damage on it.
-Pv-

[DeePsix501]

Oh, I in know way discredit this site and its vast amounts of sub lore and data. I just thought it was odd that they had information on upgrades in SH3 but didnt have it in SH4. I for one dont mind minimizing the game and looking up information on upgrades and sub data, just some people may not.

:lurk:

Personaly I have the deck gun on the back of the sub. I havent had to use it in a retreating action for self defense. When I do use it, its more for finnishing off a crippled ship, and even then I just simply adjust course slowly and bring us within about 1500 yards of the target and let the deck gun crew go at it. Having it on the back has in no way impaired my fighting capabilities. Often times, i'll try using the 20mm flaks i have on board to pepper smaller coastal boats, and they work too. Had I my choice, I wouldnt put a deck gun on if it would in some way increase underwater speed and just stick to my dual flaks, as I normaly dive to avoid aircraft rather than duke it out with them.

[WFGood]

heck that would be fun, but on the sub upgrade screen why is there two different deck guns for both the bow and stern

There were many different iterations of guns available for submarines as the war progressed. Some were purpose built for subs and others were modified from surface vessels.

The 3 inch 50 caliber Mk 21 (76mm) dual purpose cannon deck gun was standard issue on board many United States Navy Submarines, Destroyers and Destroyer Escorts (DE) during the early stages of World War II. By US Navy standards, it was generally considered to be a defensive weapon designed to be used against aircraft that were far away or very high up, although on a submarine it was primarily employed against enemy surface ships. Mounted on a pedestal either forward or aft of the conning tower, this weapon could fire a 13 lb high explosive projectile with a muzzle velocity of 2,700 feet per second and a maximum range of just over 16,000 yards with a ceiling of 21,500 feet. This gun could elevate to 85° and depress to 10°. Cartridges were packed four to a box, the weight of a full box being about 125 lbs with cartridges weighing approximately 32lbs each. The 3 inch 50 had a watertight tampion for the muzzle and a watertight cover for the breech with stainless steel mechanisms and bore. This weapon could be used with equally deadly effect against both surface and aerial targets.

The largest weapon carried aboard a US submarine was the 5 inch 25 caliber (MK40) cannon. Housed on a moveable mount, submarines located these weapons abaft of the cigarette deck.
This weapon was as efficient in laying down a barrage of anti-aircraft fire as it was in delivering salvos during shore or vessel bombardments. Semi-automatic and rapid firing, it allowed the crew to fire an average of 10 to 15 rounds per minute. This cannon was capable of sending a 54 pound projectile 18,000 yards and possessed a maximum aerial range of six miles.

The bit about the largest weapon is a little inaccurate, but I think it refers to regular fleet service. The Argonaut and Narwhal both had 6" guns.

[Sailor Steve]

Here is some better information. "Better" as in Campbell's book is considered the best on the subject. Note especially the maximum range and AA ceiling.
http://www.navweaps.com/Weapons/WNUS_3-50_mk10-22.htm
http://www.navweaps.com/Weapons/WNUS_5-25_mk10.htm

[Platapus]

The 3 inch 50 caliber Mk 21 (76mm)

The largest weapon carried aboard a US submarine was the 5 inch 25 caliber (MK40) cannon. Housed on a moveable mount, submarines located these weapons abaft of the cigarette deck.

In this context what does the calibre designation mean?

I thought I read a long time ago that it was the ratio between the bore and the barrel length. But that can't be right as the 3 inch 50 cal would be over 12 feet long.

So what does it mean when the 3 inch gun had a 50 calibre designation?

[WFGood]

Caliber. (a) The diameter of a gun's bore; (b) the nominal length of its bore, expressed in multiples of its diameter. This expresses the length of a piece in proportion to its bore; a gun described as 18 caliber's long would have a bore 18 times as long as its diameter. This term is still used today.

Both definitions are still used, although definition (a) seems to be more prevelent.

[panthercules]

The 3 inch 50 caliber Mk 21 (76mm)

The largest weapon carried aboard a US submarine was the 5 inch 25 caliber (MK40) cannon. Housed on a moveable mount, submarines located these weapons abaft of the cigarette deck.

In this context what does the calibre designation mean?

I thought I read a long time ago that it was the ratio between the bore and the barrel length. But that can't be right as the 3 inch 50 cal would be over 12 feet long.

So what does it mean when the 3 inch gun had a 50 calibre designation?

Based on the pictures of this particular gun (see here: http://www.valoratsea.com/350.htm ) and other such pictures, I wouldn't think it odd for this gun to be a little over 12 feet long, so I think that must be the way the "caliber" term is being used in this context - I think for small-bore weapons (pistols, rifles, machine guns, etc. of .5 inch diameter or less) it's more commonly used to refer to the bore diameter, but for naval guns/artillery pieces or other large bore weapons it seems to be uniformly used to denote the length instead.

[Platapus]

Based on the pictures of this particular gun (see here: http://www.valoratsea.com/350.htm ) and other such pictures, I wouldn't think it odd for this gun to be a little over 12 feet long, so I think that must be the way the "caliber" term is being used in this context .

In looking at that site, I could imagine the barrel of the 3 inch 50 calibre gun being 12 feet long. I just imagined it to be more 6-8 feet long. But in those pictures it seems a lot longer (assuming that the gun crew was not midgets)

hmmm midget gunners sleep two to a bunk and eat half the food... this might just work :rotfl:

[OddjobXL]

I'm going through the Barb's last patrol in "Thunder Below" and they didn't seem to be shy about using the cannon for aggressive purposes and it was mounted forward. Early on it seems they're using it for target practice on sampans and the like but during this patrol there's an episode where they surface, very stealthily, during a dawn attack on an armed trawler with a 40mm and 75mm cannon mounted along with "possible" machinegun positions.

They came up so that the sun was framing the trawler and they'd be on the dark side of things. From the description it seems standard practice was a very noisy affair but this time Fluckey explicitly told everyone to be silent as possible. When they were ready the the crew opened up on the enemy's weapon positions. The plan was the cripple it and then board to seize charts and possibly a prisoner for better regional intelligence. (Their mission was to "raise a ruckus" and distract Japanese anti-sub defenses from a coordinated wolfpack infiltration elsewhere).

Then again, Fluckey seems like a real nut. This same mission he'd taken rockets, the only ones in Hawaii, along for an experimental run at coastal bombardment of a fortified cable station (he claims this is the first time a submarine ever used rockets but thanks to GWX's fine manual it seems the Germans were using the same tactic years earlier on the Black Sea against the Russians). He also tries to "invade" an isolated Japanese seal farm/observation post in order to plant a flag on Japanese territory as there was a cameraman along. Well, seems a Japanese combined navy/army unit was there and a real firefight broke out. The sub again used AA and cannon to rip the hell out of any building with an antenna, first, and then they blew up any cannons observed. Took out several buildings and bunkers too! But the landing was called off as too risky.

The Japanese later claimed they came under bombardment from six capital ships...

[Sailor Steve]

In looking at that site, I could imagine the barrel of the 3 inch 50 calibre gun being 12 feet long. I just imagined it to be more 6-8 feet long. But in those pictures it seems a lot longer (assuming that the gun crew was not midgets)

hmmm midget gunners sleep two to a bunk and eat half the food... this might just work :rotfl:
Take another look at this one:
http://www.navweaps.com/Weapons/WNUS_3-50_mk10-22.htm

Gun Length oa 159.7 in (4.055 m)
Bore Length 150.3 in (3.816 m)

That's a bore length of 12 feet 6.3 inches, and an overall length of 13 feet 3.7 inches. Right on the button, it looks like to me.

[Platapus]

[quote=Sailor SteveGun Length oa 159.7 in (4.055 m)
Bore Length 150.3 in (3.816 m)

That's a bore length of 12 feet 6.3 inches, and an overall length of 13 feet 3.7 inches. Right on the button, it looks like to me.[/quote]

That fits the bore/length ratio of 50. Thanks for clearning that up. It was bugging me for a while.

[Tarl]

Ran thru the first part of my career with the deck gun aft. I was able to use it quite effectively but if the enemy was foreward had to engage at an angle allowing the gun to target either the starboard or port side. Once I graduated to the Gato and was able to install it fore I did so. Now I can engage from straight on with alot of latitude on attack angles.

No regrets here. I aggressively use it for surface attacks with defenseless enemy vessels or finishing off damaged ships.

Up front for me. :)

[Grunt]

I usually go with aft mounting, this way I can (in theory) run away full speed while also plinking away with the deck gun. Worked great in SH3.

[TheSatyr]

I'm not sure if it's modeled in game,but later in the war they would often mount a main gun and an AA gun on the 2 hardpoints. (1 forward 1 aft). I think the AA gun was another 40mm but I'm not sure about that.

[basilio]

But since you're upside down on the five incher, who wants to man it anyway??

I noticed it too.....
I'm a bit confused, is this a known bug?
I made a search but was not able to find the answer
EDIT: found the answer.
It is a known bug
See here
http://www.subsim.com/radioroom/showthread.php?t=111315