I do! Our 18" guns were successfully tested and were 47calibers in length. They could have been fielded in the Iowa-class by modifying the 16" three-gun turret into a two-gun turret to maintain weight equivalency. However, there would have been lots of trade-offs that would have likely not been a good idea. It is stated that the teak would have to be removed, because it would not survive the overpressure at the muzzles if the barrels were firing over the deck. The 20psi the 16" guns produce near the guns would be almost doubled. The unarmored (non-decapping plated areas) skin of the ship would begin to suffer battering effects, and of course, the ship would still be protected only against 16" fire. The interior of the turrets and projectile flats would have to be removed and rebuilt, and rate of fire would be decreased.Cliffy B wrote:
It'd be interesting to know how well their 18" and our own 18" fared during the testing phase. Anyone know?
I do not remember seeing it in Friendman's Battleship book, but I read the Montanas were considered to carry 8 such guns. Since it wasn't in Friendman's book (or I did not read it at least) I don't know if it's true, nor if it would be worth it. They did the whole 16"/56 caliber thing, too by lining one of the 18" test guns with a 16" liner, boosting the range of the projectiles. However, beyond 26miles the projectiles begin to deflect (right to left error) to much, and the gun barrel was still heavy as hell! The 18" barrel was not chosen because its weight, slower rate of fire, and a 9 gun salvo by 16" guns was greater than 6 18" and the same with the Montana variant: 12 16" guns versus 8 18".
So, would it be worth it? In 1940s, no. The big idea then was broadsides producing large groupings of shells to increase the chance of hitting another ship, reloading and shooting again. In the 1980s, we got really, really good at firing one round at a time at shore targets and doing on-shot-one kill with ballistic, unguided 16� rounds. If we were to use guided rounds, an 18� round provides a whole, whole lot more payload than a 16� round, and you don�t theoretically need a super high rate of fire. In the 21st century would the 18� gun be worth it? Hmm, maybe new construction, yeah.
So, then the kick @$$ question is: if we built new major caliber systems, do we build new major caliber weaponry as cheaply as possible, which is simply repeat how the Iowas do it or do we try to utilize new technology for either auto loaders with semi-fixed or fixed ammunition?
So, yes, we fully developed an 18�/47caliber naval gun. We just never had anything to put it on, nor was it worth the effort with fewer than 9 guns.