Re: Tirpitz shelling New York
Posted: Tue May 22, 2012 2:09 am
I looked at it, though I'm not sure what to make of it. Is this explaining how the USN's 14"/50 AP shells would behave badly in high obliquity?alecsandros wrote:for comparison with US 14"/L50 and US 16"/L45 2240lbs:
http://www.navweaps.com/index_nathan/Pe ... States.htm
Look at "US EFF", distance 20000 yards for all guns.
I was actually influenced by that same writer - Okun? - on the virtures of the 14"/50, when it comes to penetrating armor:
The best all-round WWII armor-piercing projectiles were the U.S. designs. They were less able to remain in effective bursting condition after penetration than British projectiles, but they remained rigid under very difficult impact conditions and could penetrate armor of much greater thickness at much higher obliquities than anyone else's. For example, at least one WWII U.S. 14" Mark 16 MOD 8 capped armor piercing projectile (APC in British and U.S. Army nomenclature, but AP in U.S. Navy nomenclature, since the U.S. Navy assumed an AP cap was always used on a "true" AP projectile) penetrated intact through a WWII U.S. 13.5" (343 mm) Class 'A' plate at 49o obliquity at barely above the NL, which far exceeded any foreign design capability that I know of.
German armor-piercing projectiles were good at penetrating armor at low obliquity (under 30o), but their ability to penetrate or remain in effective bursting condition afterwards dropped off quite rapidly as obliquity increased, especially against thick (over projectile diameter in thickness) armor.
British projectiles were very good at low obliquity (under 35o) against plates up to their diameter in thickness. At higher obliquity against such plates, they broke up or glanced off or both. British armor-piercing projectiles were even worse than German projectiles against thicker plates at all but nearly exact right-angles impacts. For example, the 14" size was found in post-WWII U.S. testing to be absolutely incapable of penetrating the thick U.S. Class 'B' turret faces or Class 'A' barbettes (17.3-19.5" (439-495 mm) thick) at even a moderate 30o obliquity, bending into "bananas" and breaking rather than punching through at striking velocities at which the equivalent U.S. 14" Mk 16 MOD 8 armor-piercing projectiles were staying rigid and passing right through, though the U.S. projectiles were usually rendered ineffective unless they penetrated at well above the NL. Neither British or German projectiles were designed for use against such heavy armor and had larger explosive charges for increased damage on penetration than the U.S. projectiles had. This lower capability of British and German projectiles seems to have been a lingering result of the restrictions of the Washington Naval Treaty of 1922, especially for the British