Fragmentation Warheads

[ranger9000]

So I know that historically these weren't really a thing by the era of the game we're in (to the best of my knowledge) though I do know some combined target anti air/anti ship missiles did and still do. But why didn't ships ever use fragmentation shells against eachother. Given the relatively unarmored superstructures, you would think such shells would potentially be exceedingly good at damaging things like fire control, funnels, and the bridge crew, and giving a higher hit rate then HE shells probably.

Things like air burst shrapnel shells, or the 18 inch or 15 inch AA shells. I'd have to guess it comes down to fuzing initially, but as I said earlier I know a few SAMs are capable of targetting warships with this type of damage in mind. Even if it still is generally a secondary option to hitting the foe with proper anti-ship missiles.

Is there any more grand explanation or is this about it.

[Adseria]

Don't quote me on any of this, because it's mostly just speculation (read: guesswork) on my part, based on my limited knowledge of the era.

The first this I want to mention is that there are a few examples of frag shells being used in the period covered by the game. The main one I can think of is the Japanese ships attempting to bombard Henderson Field on Guadalcanal in 1942 (in fact, they used the san-shiki AA shells you mentioned). They were caught by an American squadron, and it took them time to switch to AP for ship-to-ship combat. Notably, Hiei and Kirishima scored several hits on the heavy cruiser San Francisco, which caused less damage than AP would have. Damaging superstructure is useful for stopping a ship from shooting, but the only way to sink them is to damage the hull.

You mentioned that you thought there'd be problems with timing the fusing; up until WW2, that would have been true; these days you could use radar, in the same way as an airburst shell. Fusing wouldn't be the problem; the problem would be the amount of damage inflicted by a hit.

Ships in the period generally fitted into one of 3 classes: heavy ships, light ships, and carriers. "Heavy ships" includes ships like battleships and heavy cruisers, "light ships" is light cruisers and destroyers, and "carriers" is pretty self-explanatory. Generally, these ships would be expected to fight against the equivalent ships in the enemy fleet. So, equipping heavy ships with a large proportion of HE for their main battery wouldn't make much sense; better to carry more AP, and leave the smaller ships to the secondary armament.

It's also worth mentioning that fragmentation shells would cause an additional logistical problem; it's a third type of shell to worry about; it would need to be designed, developed, and mass-produced, and then it would need to be delivered to front line bases, and the end result wouldn't provide a significant improvement over the HE shells that are already in use anyway. In the end, there just isn't much point; it would be a big expense in time and money, with no real purpose.

[rimbecano]

Both AP and HE rounds used in naval warfare had fragmentation effects. They weren't quite as fragmentation-optimized as land-artillery fragmentation rounds because any steel ship, even unarmored, is going to be a harder target than an infantry column. But if you look at battle damage, e.g, from Jutland, you'll see plenty of splinter damage. Also, at the battle of the River Plate, all but three of the bridge crew on Exeter were killed by shrapnel from a hit on B turret (Graf Spee was firing HE).

[Antediluvian Monster]

As rimbecano states, fragmentation is kind of an unavoidable consequence of burst of an explosive filler in cavity within steel object. As I recall, larger filler will result in more numerous smaller fragments with higher initial velocity (but they tend to lose that velocity faster) while smaller filler will result in fewer, more massive and slower fragments.

That being said, I do belive in the early years of the game some navies (at least British) would still be issuing time fuzed shrapnel/case shells (as in shells filled with lead balls that would scatter on burst), though I have never heard of them being used in ship-to-ship combat. These were issued all the way to the 16 inch rifles on HMS Inflexible.

[polygon]

Jun 22, 2020 15:17:50 GMT -6 Antediluvian Monster said:

As rimbecano states, fragmentation is kind of an unavoidable consequence of burst of an explosive filler in cavity within steel object. As I recall, smaller filler will result in more numerous smaller fragments with higher initial velocity (but they tend to lose that velocity faster) while smaller filler will result in fewer, more massive and slower fragments.

That being said, I do belive in the early years of the game some navies (at least British) would still be issuing time fuzed shrapnel/case shells (as in shells filled with lead balls that would scatter on burst), though I have never heard of them being used in ship-to-ship combat. These were issued all the way to the 16 inch rifles on HMS Inflexible.

I imagine what's essentially 16" buckshot would do unfortunate things to any destroyer or torpedo boat unlucky enough to be hit.

[skoggatt]

Jun 22, 2020 17:44:56 GMT -6 polygon said:

Jun 22, 2020 15:17:50 GMT -6 Antediluvian Monster said:

As rimbecano states, fragmentation is kind of an unavoidable consequence of burst of an explosive filler in cavity within steel object. As I recall, smaller filler will result in more numerous smaller fragments with higher initial velocity (but they tend to lose that velocity faster) while smaller filler will result in fewer, more massive and slower fragments.

That being said, I do belive in the early years of the game some navies (at least British) would still be issuing time fuzed shrapnel/case shells (as in shells filled with lead balls that would scatter on burst), though I have never heard of them being used in ship-to-ship combat. These were issued all the way to the 16 inch rifles on HMS Inflexible.

I imagine what's essentially 16" buckshot would do unfortunate things to any destroyer or torpedo boat unlucky enough to be hit.

The British actually tried a 12" canister shot in the early 20th century for use against destroyers, but they found it wasn't very effective and it damaged the rifling of the barrels too much to be worth it.

[ranger9000]

Jun 22, 2020 12:14:54 GMT -6 rimbecano said:

Both AP and HE rounds used in naval warfare had fragmentation effects. They weren't quite as fragmentation-optimized as land-artillery fragmentation rounds because any steel ship, even unarmored, is going to be a harder target than an infantry column. But if you look at battle damage, e.g, from Jutland, you'll see plenty of splinter damage. Also, at the battle of the River Plate, all but three of the bridge crew on Exeter were killed by shrapnel from a hit on B turret (Graf Spee was firing HE).

Yeah splintering and fragments coming off of regular AP and HE shells is a thing but I was more refering to the idea of purpose built shrapnel shells like ground artillery used/uses which a few people have referenced being on some British warships. Also things like using the AA beehive shells against ships (I knew they were used against land targets but didn't know they were used against warships to any degree.)

Seems like they were ineffective in practice though. I had figured that against what amounts to sheet metal on some of the superstructures for warships (or much of the entirety of the ship for destroyers) the fragments would have been more effective at ruining everything but the turrets above the weather deck then they apparently were

[wlbjork]

The British certainly had access to shrapnel shells during WW2. In May 1944 HMS Wanderer encountered an E-boat. Lt Commander Bob Whinney ordered the use of shrapnel shell, 3 rounds of which left the enemy craft ablaze.

Of course, E-boats, being smaller (sub 200t IIRC) vessels would be more vulnerable to such weapons.

[akd]

I recall the Brits doing some trials with Shrapnel as an anti-TB measure, but not finding it effective compared to HE. Will have to dig for the reference, but I'm sure it was in something by Friedman.

[xt6wagon]

Jun 23, 2020 0:49:32 GMT -6 wlbjork said:

The British certainly had access to shrapnel shells during WW2. In May 1944 HMS Wanderer encountered an E-boat. Lt Commander Bob Whinney ordered the use of shrapnel shell, 3 rounds of which left the enemy craft ablaze.

Of course, E-boats, being smaller (sub 200t IIRC) vessels would be more vulnerable to such weapons.

Was it main gun or secondary ammo? I could see shrapnel "5in" class shells being tried, and kept on board. Main gun is harder to understand them getting past the proving grounds. 

I'd love to see the test data for ww2 spec proximity fuse. Is there an altitude where it would trigger on a small ship but not the water. 

[rimbecano]

Jun 23, 2020 0:49:32 GMT -6 wlbjork said:

The British certainly had access to shrapnel shells during WW2. In May 1944 HMS Wanderer encountered an E-boat. Lt Commander Bob Whinney ordered the use of shrapnel shell, 3 rounds of which left the enemy craft ablaze.

Of course, E-boats, being smaller (sub 200t IIRC) vessels would be more vulnerable to such weapons.

That doesn't actually establish that the shrapnel effect of such shells was amplified enough over normal HE to make them worth including in the game as a separate type. Fires can be expected from any HE round.

[akd]

Correction, it was in Brown’s Warrior to Dreadnought:

“Firing against torpedo boats and destroyers

A considerable number of trials were carried out with a wide variety of guns and projectiles to find the best way of sinking or disabling an attacking torpedo craft in the short time it was in range and before launching its torpedo. In 1889 a large replica torpedo boat was built at Shoeburyness. One-pounder shells were found to be ineffective, whereas 3pdr common shells were satisfactory when fired against the broadside but ineffective in the more realistic end-on shots, bursting long before they reached the vitals. Further trials were held in 1894-95 with 6pdr and 12pdr shells. The conclusion was that only the 12pdr could be relied on to stop a torpedo boat with a single shot. Presumably, this led to the adoption of 12pdrs as the Dreadnought’s anti-torpedo boat armament. Tests were also carried out in 1895 to see if the boilers of torpedo boats could be protected by hanging the spare fire bars on the bulkhead – ‘… the results were not encouraging’.

The old destroyer Skate was used for further trials in 1906 against 3pdr, 12pdr and 4in (25lb shell). The ship was moored so that she was either end-on to the line of fire or 13° off the line. The 3pdr was ineffective in end-on fire, many rounds glancing off the sides, and even at 13° it was thought that damage would not cripple the torpedo boat.

The 12pdr caused much more severe damage but this time the conclusion was that it could not be certain of disabling a destroyer with one hit. The 25lb shell of the 4in gun caused severe damage. There was a marked difference between the effects of Lyddite and powder-filled shell, the former making a much bigger hole when bursting on the side whilst the bigger splinters from the powder-filled shell caused damage over a greater extent. It was concluded that either powder-filled or Lyddite 4in or 12pdr would disable the destroyer if the engine-room were hit but, outside the machinery, Lyddite shell had a far better chance of disabling or sinking.

A large number of trials were carried out using shrapnel shell from guns of 6in to 12in. The object was to determine the optimum size of ball to disable the craft or its crew. Though severe damage was caused in some cases, the danger area was quite limited and it was thought that it was unlikely that the fuse would function with sufficient accuracy at the short ranges involved. Even case shot, fired from a 12.5in RML, was tried and rejected because of the likely damage to the rifling of the gun.”

[wlbjork]

Jun 23, 2020 14:46:17 GMT -6 xt6wagon said:

Jun 23, 2020 0:49:32 GMT -6 wlbjork said:

The British certainly had access to shrapnel shells during WW2. In May 1944 HMS Wanderer encountered an E-boat. Lt Commander Bob Whinney ordered the use of shrapnel shell, 3 rounds of which left the enemy craft ablaze.

Of course, E-boats, being smaller (sub 200t IIRC) vessels would be more vulnerable to such weapons.

Was it main gun or secondary ammo? I could see shrapnel "5in" class shells being tried, and kept on board. Main gun is harder to understand them getting past the proving grounds. 

I'd love to see the test data for ww2 spec proximity fuse. Is there an altitude where it would trigger on a small ship but not the water. 

Main gun - 4.7". HMS Wanderer started life as a V&W class Destroyer, then underwent conversion to the Long Range Escort variant around the time Whinney took command.

Details are in his auto-biography "The U-Boat Peril", along with his mass slaughter(!) of enemy U-boats...and a friendly fire incident