Mine is bigger than YOURS!

[Steve Smith]

Ahh...I was basing my thoughts on this pic:

Which makes it very difficult to see just how big the turret is. Thanks much.

 

[Mike in VA]

I'm with you, Larry. My own ignorance stuns me sometime, and I think I learn more here than at skul.

A most interesting thread, thank you all. Today's lesson: they's guns, and they's GUNS.

 

[Mike Irwin]

Hum...

You know, I'm going to go back on myself a little bit...

Thinking about it even more, and digging up EVERY mentally stored image I have of heavy BB guns being loaded, I'm going to slightly modify my answer, and say that the guns could probably come a lot closer to the rear of the turret than I originally though.

The crew would need clear access to the breech of the gun, that is true, but the shells and powder bags load from the side, not the rear.

They come off of hoists into trays at the side of the breech.

As long as there's enough room at the rear of the gun for the shell and powder bag tray, distance to the rear turret wall may not be as important for the gun crew as side clearance.

At one time I saw plans for an American 16" turret, but now I can't find them...

Here, however, is a very nice photograph of the breech assembly of a British 12" Naval Rifle on HMS Illustrious, again from www.warships1.com, copyright John Roberts.

 

[K80Geoff]

Jeez, you guys are too good!!!


Here is a site with some info about 16" guns, but no turret info:

http://www.geocities.com/CapeCanaveral/Hall/4634/16ingun.html

 

[Gonzo_308]

Funny I came across this thread after having lunch with my Uncle 11/11/02.

He was a plank owner on the Newport News.

He said originally the guns were slaved to RADAR for AA use.

The problem was that they moved too slowly to be effective tracking the newer jet aircraft. They were fitted with bigger faster motors to slew the turrets and that became a problem!

Something about a turret that size tracking independantly made the crew very nervous. This is also before the guns were fully automated and required a gunner and AG inside.

This is from my uncle mind you and I don't intend to argue the finer points of naval gunnery with anyone with conflicting information.

 

[K80Geoff]

OK Mike Irwin! If you click on "Naval Technology" on the Warships1 one site and scroll down to "The Nathan Okun_Naval Gun/Armor Data Resource" there is a cutaway of a triple gun turrett barbette. Kinda small but gives you an idea how the gun operated.

I am not able to copy it here, perhaps someone else can.

 

[Futo Inu]

Wowee! Now why would any military NEED a semi-auto gun that big, whose only purpose is to kill. Oh yeah, I remember - to kill.

Hmmm, the ultimate wildcat - the 8-.17 Ackley Improved. For shooting swallows flying at 30,000 feet. Now that's one steep neck.

 

[Tamara]

Who here thinks that that superposed dual 5" GP turret is just the coolest thing since sliced bread?

 

[Mike Irwin]

Then you should just LOVE this superimposed setup, Tam!

That's from around the turn of the 20th century, the pre-dreadnaught Georgia, BB13.

The top guns trained with the bottom guns, they weren't separate turrets.

The lower guns are 12", the uppers are, I believe, 8".

All in all, NOT a successful design.

Ammunition supply for the upper guns alone must have been a real pain in the butt.

 

[Mike Irwin]

Geoff,

Found a larger version of it!

Steve,

WOW! This should give you a pretty good indication of how far into the turrets the guns extended, the available working areas for the crew (not much), etc.

I had NO idea that this much of the turret was given over to equipment!

OK, this image isn't working, so I'm going to try to reattach it elsewhere.

 

[Mike Irwin]

OK, for some reason the image doesn't seem to be slaving.

To display the turret diagram, right click on the image, and select "show picture."

 

[Brian Williams]

IIRC the guns on the U.S. Iowa class battleships used 3, 200 pound bags of black powder to send their 2700 pound HE shells out the barrel. No case, just soft lead plates in between the bags to keep them from burning to fast.

This is one of the reasons the Arizona expolded with the force it did because the bombs or torpedos hit the black powder magazine.

 

[Mike Irwin]

Perfesser,

Well, no.

The propellant bags were a bit heavier, about 220 pounds, but were NOT black powder. They were a smokeless, nitrocellulose-based powder not unlike today's propellants.

Blackpowder was used in small quantities as a booster at the ends of the bags, but it was only a small amount of the charge by weight, probably not even 5%, if that much, but I believe its primary use was as fusing and as an initiator at the rear of the main charge.

The reason the Arizona exploded so violently is that the bomb hit one of the magazines and ended up setting off nearly 1 million pounds of smokeless propellant. It is thought that the blast did start in the black powder magazine, which flashed into the adjacent smokeless magazine, but the amount of black powder that went off was probably only a few thousand pounds, at most.

Had that amount of black powder exploded, Arizona would have been shattered instead of just being torn. Black powder is actually an explosive, whereas smokeless powder is a flammable solid.

 

[sven]

My vote for "Thread of the Year"

 

[Mike Irwin]

Perfesser,

Whoops, my bad.

The propellant for the 16" main guns was in SIX bags of about 110 lbs. a piece.

 

[Mike Irwin]

OK, here's the image of the turret that I was talking about...

OK! That's better!

 

[Steve Smith]

Thanks, Mike. Like you, I had no idea. That is impressive!

Its a shame that I had a tour of the USS North Carolina at such an early age, or I'd remember this stuff!

 

[K80Geoff]

Go ahead punk, make my day

 

[Mike Irwin]

Ah, the Nagato.

I think she was the only Japanese battleship, and possibly the only first-line capitol ship, to survive the war.