Comments by "Sar Jim" (@sarjim4381) on "HSwMS Tre Kronor - Guide 107" video.

Both of these cruisers belied their Italian origins in their turret designs. They suffered the same excessive shot dispersion problems as the Italians due to the barrels being mounted too closely together. Swedish 6" ammunition was better quality, and some changes were made to how a salvo was fired. One barrel fired a few hundredths of a second sooner than its opposite barrel. That helped, but it never totally solved the problem. I'm not aware of any Swedish results of using the main armament as dual purpose, but I suspect it wouldn't have been any more successful than what was seen in the USN Worcester class DP cruisers. The Tre Kronor class were constructed to a budget rather than to maximize their lethality. The goal was for a 33 knot vessel, with the same SHP as a Brooklyn but only powering two shafts rather than the Brooklyn's four. Even though the length of the Tre Kronor was virtually identical to the Brooklyn, the hull was more finely designed, with a beam seven feet narrower than a Brooklyn. While that meant the goal of a 33 knot top speed was accomplished on two shafts, it had other undesirable effects. The narrower beam meant the Tre Kronor could carry less armor per foot of length as any more armor would have reduced top speed. Some of the weight of what was available for armor had to be allocated to the ice strengthened bow. Consequently, she only had a 2.8" belt and a total of 1.2" of deck armor. This compares to the 3 1⁄4–5" of belt armor and 2" of deck armor of the Brooklyn. Turrets were even worse, with Brooklyn having a 6" turret roof and not more than about 4.5" on the Tre Kronor. Conning tower armor was the one place the two ships were more or less equal. It's probably a good thing that the ex-Tre Kronor never met the ex-Brooklyn in combat. The armor disadvantages combined with a weak seven gun broadside compared to the ex-Brooklyn's fifteen guns wouldn't have contributed to a good outcome for the ex-Tre Kronor.
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@orangelion03 You're welcome. I can't confirm this, but I believe the are an early version of a Bofors 103 mm illumination round launcher. Later versions were turret mounted on several Canadian destroyer classes.
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@orangelion03 You're welcome. As I wrote, I can't find any information in my books or online to confirm it, but the launchers are too small to be anti-submarine rockets, so illumination rounds are the only thing that makes sense to me. They could also be dual purpose chaff/illumination launchers.
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