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Deck Gun tactic question

OK, I know the German deck gun tactic was to only use it on crippled ships, to "finish them off'", and eventually they stopped using the deck gun altogether. What is the US tactic? For example, I am stalking a smallish costal merchant near the Japanese coast. Should I surface and hit him with the guns, since he is smaller, or will he call for help and I will get tons of planes/patrol ships/etc. after me? Just wondering how often the gun was used, as it seems like it was used more by the US then their German counterparts

Why don't you find out? Be the first one to inform us of how it works.:D

Who dares wins, baby.:up:

Quote:

Originally Posted by hmatthias

Unless the submarine is unable to dive, combatant ships should not be engaged by gunfire, except they be of the small patrol type (more dangerous because of their depth charges than because of their guns), definitely preventing the accomplishment of a vital mission. In the latter case, the probable chance and relative advantage of possible destruction of the patrol vessel must be weighed against the disclosure of the submarine's presence or position, and the probable damage that may be received. Gun attacks on important merchant vessels will normally not be made, as the submarine will usually find itself out-gunned and at a disadvantage. When engaging surface targets, endeavor to do so as a surprise and from a position that will be poorly protected by lookouts and where the minimum number of enemy guns can bear. Engage on bearings that will permit the best service to own guns.
Conditions of Readiness. Main Battery. Keep telescopes installed at all times and guns boresighted for long range. Keep ammunition in magazine, but be prepared, when action is imminent, to advance ammunition as near gun(s) as permitted by readiness to dive without delay. In order to be prepared for surprise night gun attack, set deflection scale to compensate for drift and set range scale between 2,000 and 4,000 yards.
In establishing and maintaining hitting range and deflection, use the simplest effective control methods against both aerial and surface targets.
Against surface targets use ranging shots, spread in range, to establish hitting gun range. Maintain hitting gun range by spotting methods that cross and recross the target and that depend only on the determination of whether shots are short or over (in range).
In general, procedure for submarine gunfire is very similar to local control of a single gun, or of local group control in the case of two-gun submarines, as on surface ships. The spotter and control officer are usually combined and communication with the battery should be as simple as possible. Absence of instruments and assistants, plus low spotting heights, complicate this problem.
Considering the type of target against which a submarine may expect to effectively use its gun, ammunition supplied will normally be common and high capacity point detonating in such proportions as is found to be most useful from time to time. The high capacity point detonating projectile and fuse have been found effective against steel plating as follows:
- 3" up to 1" thickness
  4" up to 11/2" thickness
  5" up to 2" thickness
  6" up to 21/4" thickness

Regarding point 6: I was unaware that submarines in the US arsenal were using HC ammunition, as it was normally assigned for shore bombardment due to its concrete-penetrating ability. I would consider that "AP" in the game can be considered to mean High Capacity ammunition, and "HE" can be accepted as "Common".

So, I'm still pretty sure they didn't use any starshells.

Thanks for that reference, Krupp.

Quote:

Originally Posted by Sailor Steve

if it is like any of the army's shell types

AP = armor piercing
HE = high energy

Well, it's just that SH3 had several types of shells, and the best evidence is that while destroyers carried those types, u-boats were limited to HE only. I had always assumed that it was the same for US boats, but if Krupp's info is correct, then that isn't true.

we use the guns more than the germans.

the japanese used a lot of lighter ships, esp. near the end of the war, coastal frighters and such.

So whereas the Germans used their deck guns less and less, the Americans used them more and more.

Quote:

Originally Posted by Sailor Steve

Another detail:
"..., as the submarine is not equipped with gun power to equal that which may be expected on modern merchantmen. The submarine gun may be employed against vessels known to be unarmed or small vessels of minor resistant qualities. "

I was in a hurry with my post above, and forgot to add the source for that quote. That earlier, and this short one here are from a manual called "The fundamentals of Submarine Doctrine.Doctrine are derived from theWar Instructions, U.S.Navy; General Tactical Instructions, U.S. Navy; Current U.S. Fleet Doctrine and Tactical Orders" or something like that.

it would sound as if High capicity point detonating would be a HE or High Explosive round, while commo woul dbe a basic kinetic/armor piercing round. I have no real basis for that, it just sounds right to me. Common could imply the simplicity in having a solid metal round, compared to a more complicated, partitioned, fused round with explosives.

Its only a guess though.

Quote:

Originally Posted by Sailor Steve

From http://www.navweaps.com/Weapons/Gun_Data_p2.htm :

Quote:

Common - Common or special common were originally shells - which literally means a hollow container - filled with black powder and used for attacking lightly armored or unarmored vessels. By the 1930s, this term was used by a few navies to describe any non-armor piercing shell. By that time, the bursters were less sensitive explosives, such as TNT.

HC - High Capacity. A projectile for use against lightly armored targets. Contains a relatively large amount of explosive as compared to an armor piercing projectile.

So, are these two types of ammo, as described above, really one in the same? Should we even then have AP ammo on board our subs?