Furutaka-class cruiser rebuilt as Light cruisers?

[torten]

This a bit niche even by the Forum's standard, so I will include a Wikipedia link to the relevant ship class.
https://en.wikipedia.org/wiki/Furutaka-class_cruiser

The Furutaka class cruisers were rebuilt with three dual eight inch turrets in the late 1930's, replacing six 8 inch single turrets. My idea is that they are given three triple six inch turrets instead.

Is their any massive problems with this? Of course, this means Japan could build two heavy cruisers in the place of two Agano class ships if so desired, which might be smaller than other heavy cruisers of the period.

Thoughts?

 

[RamscoopRaider]

Doctrinally it doesn't fit. Furutaka's were A Type Cruisers, essentially they were for fleet scouting and for nighttime torpedo attacks on the US battleline as a prelude to the decisive battle. The Light cruisers were B and C type and were designed as flagships for destroyer and submarine squadrons, the Furutaka's AFAIK lack that provision. So they would be used in the role of A type Cruisers whatever their main armament, and as part of their job would be fighting past US cruisers to get a shot at the Battleships, the 8" gun is better against cruisers and would serve them better, note what they did with the Mogami's. Interesting Idea, don't think it fitw with doctrine

 

[CalBear]

Doesn't much matter in the end. The reduction in firepower in broadside is 373 pounds, range is, in practical terms, identical given the state of IJN radars (anything at much past 20K is more luck than skill). Navweaps notes that the 15.5cm had a much tighter dispersion than the 20cm/50 gun, so the chances of a hit are better with the lighter gun. Navweaps also notes that the ships ammunition handling set up was very poor (as might be expected of a design of this era) so rate of fire will be abysmal regardless of gun mounted.

The class itself is so old that the CL vs. CA designation really doesn't make that much difference.

 

[CV12Hornet]

On the technical side of things, information on Navweaps indicates that the 155mm triple required a somewhat larger barbette than the twin 8", but given the barbettes are being rebuilt anyway that's probably not too much of a hindrance.