FRN7 and FRN8

[hussar62]

I have 2xFRN7 and 1xFRN8 that I am about to start constructing. Both of these are 8" gunned cruisers and looking at the main turrets for these models they seem a bit small. In fact they are smaller than any other 2 gun 8" turrets when compared to other GHQ models with that configuration. I have looked at my reference (M.J. Whitley "Cruisers of World War Two") but I cant tell from the line drawings or text if the turrets were indeed smaller than their contemporaries from other navies. Is there anyone out their who is knowledgeable on the French Navy who could confirm their 8" gun turret designs were actually smaller?

[StarCruiser]

The turrets on both classes (Suffren and Algerie) were fairly small by most standards.

https://en.wikipedia.org/wiki/Suffren-class_cruiser

https://en.wikipedia.org/wiki/French_cr ... g%C3%A9rie

I think the GHQ models look fairly close.

[kiasutha]

My copy of "Janes" was handy, so I took a look there.
Both the drawings and photos seem to show unusually small main turrets.

[CBoy3]

Naval things are not my main area of interest, but when the guns are referred to as 8" doesn't that refer to the caliber of the projectile? If so, then 8" is the size of the hole that the shot is coming out of, so comparing the overall size of the turrets to other 8" turrets shouldn't make any difference unless the turrets being compared were of the exact same type. With these being French ships I don't think that comparing the overall size of the turrets to those of different ships of other nations, or even French ships that used different 8" turrets, would make any difference.

[Mk 1]

Naval things are not my main area of interest, but when the guns are referred to as 8" doesn't that refer to the caliber of the projectile? If so, then 8" is the size of the hole that the shot is coming out of ...

Correct. These were heavy cruisers, with 8-inch guns (more often described as 200mm or 203mm or 20cm guns in most of the world).

... so comparing the overall size of the turrets to other 8" turrets shouldn't make any difference unless the turrets being compared were of the exact same type. With these being French ships I don't think that comparing the overall size of the turrets to those of different ships of other nations, or even French ships that used different 8" turrets, would make any difference.

The issue is that 8-inch guns are big guns. You can't make them small guns. You can put a big empty turret around them, but given that the turret is armored, and armor weighs a lot, most naval architects try to make turrets that are as small as they can, given the number of guns and the size of the guns (including the size of the gun crew to serve the gun, and the ammo handling mechanism). Take 5 different naval architects, give them all the task of designing turrets with the same amount of armor fitting the same number of guns of the same caliber, and you'll probably get 5 turrets of very similar size.

Similar. Not identical. And probably. Not definitely.

So when one country uses noticeably smaller turrets for guns of the same caliber, it raises questions. Like, how'd they do that?

Maybe they put the guns closer together because they didn't care about dispersion. Some ships were notorious for one gun's muzzle flash disturbing the accuracy of it's turret-mate gun(s).

Maybe they accepted a lower rate of fire than other nations, and so did not worry about providing enough space for the crew to effectively server the gun.

Maybe they had a better ammo handling mechanism (or smaller, even if not better). That might save space, and it also might save crew size, saving space.

Maybe the French 8-inch guns were substantially lower power than other 8-inch guns, so their breaches could be smaller (smaller chambers due to less propellant powder, smaller breaches due to thinner chamber walls, etc.).

I don't claim any particular knowledge about which of these issues were present in French CA turrets. But I believe it would not be lower power or higher dispersion. My understanding is that the Algerie, at least, was pretty well regarded for the power and accuracy of her guns.

Will be interested to see what others come up with.

-Mark

[StarCruiser]

Based on the data in (the often dubious) Wikipedia entries for the guns of the Duquesne class, as compared to other similar guns of that same era... All very similar.

The German and Italian 8" pieces seemed to have slightly higher muzzle velocities and slightly better range but otherwise..?

The rate of fire seems fairly similar at 4-5 rounds per minute.

I'd like to see some more detail on how those turrets were laid out internally...

[hussar62]

[hussar62]

As they say a picture can paint 1000 words. Pics are all GHQ models of ships with twin 8" turrets, or gun houses. Checking the NAVWEAPS web site I found the following on turret weights and type of gun:

Country Gun Turret Weight in Tons
France 8"/50 177 - 220
Italy 8"/53 178
British 8"/50 205-220
Germany 8"/60 274-288
Japan 8"/50 163-172
USA 8"/55 187

Those listed with high and low ends account for variances in armor and in some cases equipment (e.g. some had range finders others did not). The 177 ton French turret had 1.2" of Armor. The 205 ton British turret had approx. 1" of armor. The American (Pensacola's twin turret) and the Japanese were also lightly armored. So did the French really get what appears to be a smaller turret yet carry essentially the same gun? As a previous poster mentioned what did they trade off to get to this size? Or is the models turret under sized?