# Japanese Naval Rifles (WWII Leyte) - loaded with dye **URL:** \ **Category:** Factual Questions\ **Created:** [November 22, 2012, 2:36am UTC](https://boards.straightdope.com/t/japanese-naval-rifles-wwii-leyte-loaded-with-dye/641793 "2012-11-22T02:36:41Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [November 22, 2012, 2:36am UTC](https://boards.straightdope.com/t/japanese-naval-rifles-wwii-leyte-loaded-with-dye/641793/1 "2012-11-22T02:36:41Z")
In a book I’m reading (James Hornfischer’s jaw-dropping [Last Stand of the Tin Can Sailors . . .](http://www.amazon.com/Last-Stand-Tin-Sailors-Extraordinary/dp/0553381482/ref=sr_1_1?s=books&ie=UTF8&qid=1353550387&sr=1-1&keywords=last+stand+of+the+tin+can+sailors)), there is repeated mention made of the geyers of coloured spray sent up by incoming Japanese rounds. In one memorable sequence, Hornfischer recounts how one of the destroyers was like a chameleon - each time a salvo landed near, the ship would be doused in a different colour. Then the bow would dip into a wave and water would rinse the decks and gunwales clean until a shell bearing a different hue - green, yellow, red - crashed a column of seawater across her decks again. Sailors in the open would be painted similarly. But, I digress . . . In any case, one of my questions is whether all Japanese naval shells carried a dye load to indicate where they landed, or only some. And, in either case, wouldn’t the trajectory of a dye-carrying shell differ from one not so laden (especially if it only contained dye)? In other words, how confident could the Japanese be that they could adjust their aim according to where they saw the dye appear. As an aside, did the Americans also use dye-carrying shells to adjust their aim? Or did their computer controlled firing make it irrelevant? Hornfischer never mentions it. Thanks! ---
**Author:** ![SanDiegoTim](https://avatars.discourse-cdn.com/v4/letter/s/85e7bf/32.png) [@SanDiegoTim](https://boards.straightdope.com/u/SanDiegoTim)\ **Post date:** [November 22, 2012, 2:48am UTC](https://boards.straightdope.com/t/japanese-naval-rifles-wwii-leyte-loaded-with-dye/641793/2 "2012-11-22T02:48:53Z")
I can’t answer your questions, but “Tin Can Sailors” was a great read. His earlier book about Guadalcanal (Neptunes Inferno?) wass also excellent. If you like the subject, pick up Sea of Thunder by Evan Thomas. ---
**Author:** ![OttoDaFe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ottodafe/32/356_2.png) [@OttoDaFe](https://boards.straightdope.com/u/OttoDaFe)\ **Post date:** [November 22, 2012, 5:55am UTC](https://boards.straightdope.com/t/japanese-naval-rifles-wwii-leyte-loaded-with-dye/641793/3 "2012-11-22T05:55:32Z")
I can’t say for certain, but I imagine that the dye was part of the explosive charge rather than being applied to the shell casing. I don’t see how an external dye would survive being fired. As to the second question, the USN relied on its computerized fire control systems for ship-to-ship action. Combined with sheer audacity, it was probably the major factor in allowing the DDs and DEs to be as effective as they were. ---
**Author:** ![sqweels](https://avatars.discourse-cdn.com/v4/letter/s/f19dbf/32.png) [@sqweels](https://boards.straightdope.com/u/sqweels)\ **Post date:** [November 22, 2012, 6:12am UTC](https://boards.straightdope.com/t/japanese-naval-rifles-wwii-leyte-loaded-with-dye/641793/4 "2012-11-22T06:12:26Z")
The US sailors exclaimed, “They’re shooting at us in Technicolor!”. The purpose of the colored dye was so each ship could distinguish which splashes were theirs so they could adjust their aim accordingly. I’d bet most of the shells each ship had on board were the regular kind, but the dye-loaded ones were naturally to be used up first once they finally had the opportunity to fire on enemy ships. I’m sure the dye was just mixed in with the explosive charge and didn’t affect the shell ballistics at all. ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [November 22, 2012, 10:07am UTC](https://boards.straightdope.com/t/japanese-naval-rifles-wwii-leyte-loaded-with-dye/641793/5 "2012-11-22T10:07:43Z")
I’m fairly sure it was just the battleship and heavy cruiser main batteries that were equipped with the dye shells. ---
**Author:** ![Dissonance](https://avatars.discourse-cdn.com/v4/letter/d/85f322/32.png) [@Dissonance](https://boards.straightdope.com/u/Dissonance)\ **Post date:** [November 22, 2012, 3:27pm UTC](https://boards.straightdope.com/t/japanese-naval-rifles-wwii-leyte-loaded-with-dye/641793/6 "2012-11-22T15:27:51Z")
> [@KarlGauss](#): > > As an aside, did the Americans also use dye-carrying shells to adjust their aim? Or did their computer controlled firing make it irrelevant? Hornfischer never mentions it. Yes, Americans used dye-carrying shells to adjust their aim as well. Proof that Admiral Scott and most of the bridge crew of the _Atlanta_ had been killed by friendly fire in the confused night engagement of Friday Nov 13, 1942 off of Guadalcanal came in the form of [green dye](http://en.wikipedia.org/wiki/USS_Atlanta_(CL-51)#Night_Attack): > [@](#): > > Soon after being torpedoed, Atlanta was then hit by an estimated nineteen 8-inch (200 mm) shells when San Francisco, “in the urgency of battle, darkness, and confused intermingling of friend or foe”, fired at her. Though almost all of the shells passed through the thin skin of the ship without detonating, scattering green dye, fragments from their impact killed many men, including Admiral Scott and members of his staff. Atlanta prepared to return fire on her new assailant, but San Francisco’s own gun flashes disclosed a distinctly “non-Japanese hull profile” that resulted in a suspension of those efforts. San Francisco’s shells, which passed high through Atlanta’s superstructure, may have been intended for a Japanese target further beyond her from San Francisco’s perspective.