Brooklyn V Mogami

Historical what if discussions, hypothetical operations, battleship vs. battleship engagements, design your own warship, etc.
User avatar
Gary
Senior Member
Posts: 706
Joined: Mon Apr 17, 2006 3:37 pm
Location: Northumberland

Brooklyn V Mogami

Post by Gary »

Mogami AS BUILT with 15 x 6 inch guns against the USS Brooklyn who has the same firepower.

1 on 1

Am I right in saying that the USN 6 inch shell is superior to the Japanese version?
God created the world in 6 days.........and on the 7th day he built the Scharnhorst
lwd
Senior Member
Posts: 3822
Joined: Sat Jun 17, 2006 2:15 am
Location: Southfield, USA

Re: Brooklyn V Mogami

Post by lwd »

Well looking at:
http://www.navweaps.com/Weapons/WNJAP_61-60_3ns.htm
and
http://www.navweaps.com/Weapons/WNUS_6-47_mk16.htm
The US round is a bit heavier but has a lower muzzle velocity and a smaller burster. The US gun does have 3 x the estimated barrel life unlikely to effect a single combat especially if both ships have new guns but if both have fired a couple hundred rounds in each gun the Japanese gun will be showing signs of wear. The US gun is also rated at nearly twice the rate of fire. Especially in a sustained engagment where the powder hoist would limit the Japanese to 5 rpm where the US could fire 8-10 this might make the difference.
User avatar
Legend
Senior Member
Posts: 325
Joined: Tue Oct 21, 2008 12:46 am
Location: Tomahawk, Wisconsin

Re: Brooklyn V Mogami

Post by Legend »

USS Brooklyn:
Armament: 15 x 6in
Broadside: 1,950lbs
RoF: 8 rounds per minute
lbs per minute: 15,600lbs

IJN Mogami:
Armament: 10 x 8in
Broadside: 2,770lbs
RoF: 4 per minute
lbs per minute: 11,080lbs

It clearly shows that while the Mogami would have a better amount of punch, Brooklyn has a faster RoF and can put more munitions onto her target. I do not know the quality of Japanese radar, but I can assume that once Brooklyn got into range, she would get hits on Mogami quickly.
AND THE SEA SHALL GRANT EACH MAN NEW HOPE, AS SLEEP BRINGS DREAMS.
User avatar
Legend
Senior Member
Posts: 325
Joined: Tue Oct 21, 2008 12:46 am
Location: Tomahawk, Wisconsin

Re: Brooklyn V Mogami

Post by Legend »

Why cant I edit my last post? Was that privelage taken away at some point?

I realized that before 1940 the class was taken into the yards, replacing the five 6in turrets to five 8in turrets... so the data from my previous post is accurate, for by the time that all four of the ships were converted with heavier armament they would have been facing the Brooklyn class.
AND THE SEA SHALL GRANT EACH MAN NEW HOPE, AS SLEEP BRINGS DREAMS.
Bgile
Senior Member
Posts: 3658
Joined: Wed Mar 09, 2005 7:33 pm
Location: Portland, OR, USA

Re: Brooklyn V Mogami

Post by Bgile »

Legend wrote:Why cant I edit my last post? Was that privelage taken away at some point?

I meant to fix a typo with the Mogami's armament. It seems I mixed her armament up with some other cruiser in my personal file... though I cant seem to figure out which. :stubborn:

Mogami has... you know what forget it. They have fairly equal armament... On the broadsides page on Wikipedia they have Mogami's armament mixed up.
Mogami was converted to 8" guns. This thread hypothesized that didn't happen.
User avatar
Gary
Senior Member
Posts: 706
Joined: Mon Apr 17, 2006 3:37 pm
Location: Northumberland

Re: Brooklyn V Mogami

Post by Gary »

Hi all - Thanks for replying.

Yes, I was envisioning a scenerio where Japan left Mogami as a CL.

At the time of her construction, Japan was able to still build 6 inch gunned cruisers as per the Treaty limit but no new 8 inch ships.
They cleverly built the barbettes so that the turrets could be replaced with 8 inchers.
The removed 6 inch turrets historically found their way onto Yamato - so if my scenerio were true and Mogami kept her original turrets then perhaps Yamato would not have had such a vunerable secondary battery.
Apparently the Japanese always intended to convert the Mogami's to CA's (clever huh?)

Getting back to topic, I guess Brooklyn is hard to beat for a CL - she was the best of the bunch I reckon
God created the world in 6 days.........and on the 7th day he built the Scharnhorst
User avatar
Legend
Senior Member
Posts: 325
Joined: Tue Oct 21, 2008 12:46 am
Location: Tomahawk, Wisconsin

Re: Brooklyn V Mogami

Post by Legend »

You are right my friend, of all the cruisers in WWII of all nations, the Brooklyn class had the highest broadside weight and highest RoF combination, resulting in a class of ships with unparalleled firepower.

The later Des Moines CA's, Oregon City CA's, Alaska CC's, German Gneisenau, Fargo CA's, and Worcester CA's had higher fire power.
AND THE SEA SHALL GRANT EACH MAN NEW HOPE, AS SLEEP BRINGS DREAMS.
Bgile
Senior Member
Posts: 3658
Joined: Wed Mar 09, 2005 7:33 pm
Location: Portland, OR, USA

Re: Brooklyn V Mogami

Post by Bgile »

The Oregon City class were actually just improved Baltimore class CAs.
User avatar
Gary
Senior Member
Posts: 706
Joined: Mon Apr 17, 2006 3:37 pm
Location: Northumberland

Re: Brooklyn V Mogami

Post by Gary »

One Japanese officer upon witnessing the shore under bombardment from a Brooklyn class (possibly USS Helena but I cant recall) remarked "Are those guns automatic?" :clap:
God created the world in 6 days.........and on the 7th day he built the Scharnhorst
User avatar
Legend
Senior Member
Posts: 325
Joined: Tue Oct 21, 2008 12:46 am
Location: Tomahawk, Wisconsin

Re: Brooklyn V Mogami

Post by Legend »

I can see how that would be, considering that all cruisers that the Japanese used had a RoF that was half of the 8rpm that the Brooklyn had... exept for the small 5.5in ones such as Yubari and Nagara... So yes I can see how it would scare the crap out of Japanese troops!
AND THE SEA SHALL GRANT EACH MAN NEW HOPE, AS SLEEP BRINGS DREAMS.
User avatar
chcrawfish
Member
Posts: 57
Joined: Tue Dec 23, 2008 5:39 pm
Location: Fort Worth, Texas
Contact:

Re: Brooklyn V Mogami

Post by chcrawfish »

Remember...one hit near the torpedo reloads and the fat lady sings.
"Never tell people how to do things. Tell them what to do and they will surprise you with their ingenuity."
- General George S. Patton, Jr
dunmunro
Senior Member
Posts: 4394
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Brooklyn V Mogami

Post by dunmunro »

Legend wrote:You are right my friend, of all the cruisers in WWII of all nations, the Brooklyn class had the highest broadside weight and highest RoF combination, resulting in a class of ships with unparalleled firepower.

The later Des Moines CA's, Oregon City CA's, Alaska CC's, German Gneisenau, Fargo CA's, and Worcester CA's had higher fire power.
The Belfast and Colony class CLs had 12 x 6" guns firing a 112lb shell, with a maximum theoretical RoF of 12 RPM:

These turrets also had improved rate of ammunition supply via improved hosts. This allowed for a theoretical 12 RPM/gun which was, apparently, achieved in service:

Geoffrey Brooke, in Alarm Starboard describes achieving the following in HMS Bermuda, which had the MkXXIII turret/trunk design:

"...Once confidence had been gained a stop watch was produced to promote competition among the three crews. Eventually a loading cycle of four and a half to 5 seconds was attained at low elevation, another two to three seconds being required with the guns elevated for long range. The time would lengthen as fatigue set in, but was creditable." P200

Campbell states that on the Mk XXIII (long trunk design) each gun had its own shell and charge hoists, which could deliver 12 per minute per gun versus the previous Mk XXII mount which had two hoists per turret with a maximum of 32 shell/charges/minute/turret. The twin hoist arrangement would have created supply problems at the guns.
yellowtail3
Senior Member
Posts: 408
Joined: Wed Oct 28, 2009 5:50 pm
Location: North Carolina, USA

Re: Brooklyn V Mogami

Post by yellowtail3 »

I think I'd put my money on the Brooklyn, regardless of which battery Mogami was carrying. I think that the 6"/47cal was a great system for anti-surface work.
Shift Colors... underway.
User avatar
VoidSamukai
Member
Posts: 77
Joined: Thu Nov 05, 2015 11:42 pm

Re: Brooklyn V Mogami

Post by VoidSamukai »

I think that this will boil down to one question: can the Mogami close the distance and launch an effective strike of torpedoes and hit the Brooklyn. If so, than Mogami has an advantage. If not, it is anyone's guess
Post Reply