Search found 30 matches

by Billy
Tue Aug 25, 2020 2:21 pm
Forum: Naval Weapons
Topic: Anti Destroyer and Merchantmen shells
Replies: 0
Views: 308

Anti Destroyer and Merchantmen shells

See in some posts of similar battleship guns being used on land but often fired a much lighter she'll at very high velocities. Something like a 300-400 kg high explosive shell doing 3400 fps. I couldn't help but think that that would be a perfact anti destroyer or merchantman shell. One hit would wi...
by Billy
Tue Aug 25, 2020 2:12 pm
Forum: Naval Weapons
Topic: Turret weight vs calibre length
Replies: 14
Views: 1025

Re: Turret weight vs calibre length

Sorry about the double post. Internet seems slow today.
by Billy
Tue Aug 25, 2020 2:11 pm
Forum: Naval Weapons
Topic: Turret weight vs calibre length
Replies: 14
Views: 1025

Re: Turret weight vs calibre length

So what does this all mean. Using the Italian 15/40 as an example. If fired the lighter she'll it would still be doing around 2550 fps, on the rather small charge of around 150kg cordite and a large barrel life. One could trade the barrel life for increased velocity. One could also up the calibre to...
by Billy
Tue Aug 25, 2020 2:10 pm
Forum: Naval Weapons
Topic: Turret weight vs calibre length
Replies: 14
Views: 1025

Re: Turret weight vs calibre length

So what does this all mean. Using the Italian 15/40 as an example. If fired the lighter she'll it would still be doing around 2550 fps, on the rather small charge of around 150kg cordite and a large barrel life. One could trade the barrel life for increased velocity. One could also up the calibre to...
by Billy
Tue Aug 25, 2020 1:52 pm
Forum: Naval Weapons
Topic: Turret weight vs calibre length
Replies: 14
Views: 1025

Turret weight vs calibre length

Found it interesting that, in one of the comments on the forum mentioned something that got me thinking and made me look into this topic that may at first sight not be consequential to actually have rather large impacts to overall design. So what I've found is the greater the barrel length in calibr...
by Billy
Tue Aug 25, 2020 12:38 pm
Forum: Naval Technology
Topic: Brittle Fracture and torpedo resistance
Replies: 10
Views: 8508

Re: Brittle Fracture and torpedo resistance

I found it interesting in reading D.K. Brown's book, that in the initial testing phase to limit the effects of underwater explosion, a rather strong setup failed miserably. He then concludes that as the tests were done in rather cold conditions it was probably as a result of brittle fracture. This w...
by Billy
Fri Sep 13, 2019 7:27 pm
Forum: Naval Weapons
Topic: American SH shells - Famed or Folly
Replies: 33
Views: 9213

Re: American SH shells - Famed or Folly

Hi Djoser. Yes the the equation for energy is F = MV, but the equation for actual penetration is quite different, hence what would seem the rather non intuitive values. The values I got above were straight from Nathan Okuns work if I remember correctly and I presume with the help of modern simulatio...
by Billy
Thu Sep 12, 2019 11:16 pm
Forum: Naval Propulsion
Topic: Lurrson effect rudders for Bismarck?
Replies: 2
Views: 587

Lurrson effect rudders for Bismarck?

So, come across a rather interesting tidbit of information. German S boats or E boats used a very interesting arrangement to help reduce wave making resistance at speed. Basically a system whereby two outermost rudders were canted out slightly to create a cavitation bubble. The wake of the ships pro...
by Billy
Thu Sep 12, 2019 10:31 pm
Forum: Naval Technology
Topic: Brittle Fracture and torpedo resistance
Replies: 10
Views: 8508

Re: Brittle Fracture and torpedo resistance

Well going by the above compositions it seems German steel would also have been immune to brittle fracture aswell.
by Billy
Tue May 02, 2017 12:27 am
Forum: Bismarck General Discussion
Topic: 38 cm shells
Replies: 60
Views: 31573

Re: 38 cm shells

Firstly - that it turns out that British and American shells were not that similar - you are actually right. However that greater performance at NORMAL impact of British shells only serves to camoflage the inferior American armour as it gives more penetration when penetrating superior British armour...
by Billy
Mon May 01, 2017 11:47 pm
Forum: Bismarck General Discussion
Topic: 38 cm shells
Replies: 60
Views: 31573

Re: 38 cm shells

And also lets not forget accuracy. Also a not too mentioned topic. If you cant hit the target then what good is muzzle energy. From all accounts the 14 in was accurate. Although I do still really believe that the 38/52 is very underated. People say its got a light shell BUT it turns out that armour ...
by Billy
Mon May 01, 2017 11:11 pm
Forum: Bismarck General Discussion
Topic: Yaw deck?
Replies: 12
Views: 6502

Yaw deck?

The top deck of American battleships was sometimes officially known as the yaw deck. There has been much debate over the function of yawing a heavy projectile. Some people saying of course it does others decrying the notion and refer to it as normalising, where the shell direction is slightly differ...
by Billy
Mon May 01, 2017 10:44 pm
Forum: Naval Weapons
Topic: American SH shells - Famed or Folly
Replies: 33
Views: 9213

American SH shells - Famed or Folly

The use of the Very heavy 2700 lb shells have been vaunted over the years. And looking at it it has allot going for it. 1. Resonably good initial velocity - 2500fps ( for the 50 ) and awesome momentum energy values. 2. Excellent velocity retention at range. 3. Excellent deck penetration values at lo...
by Billy
Sat Apr 11, 2015 7:14 pm
Forum: Naval Technology
Topic: Brittle Fracture and torpedo resistance
Replies: 10
Views: 8508

Re: Brittle Fracture and torpedo resistance

Hi there. I sorry I've been away for quite a while. Anyway what I forgot to include was the said article for ductile brittle transition to occur under impact starts at 15 C. Then the strength of the steel declines linearly from 160 Nm all the the way down to 15 Nm at 5 C. So the colder the worse it ...
by Billy
Wed May 15, 2013 5:08 pm
Forum: Bismarck General Discussion
Topic: 38 cm shells
Replies: 60
Views: 31573

Re: 38 cm shells

To Thoresten thanks, but what I meant was that given the British shells known advantage at normal incidence and the angle of fall at that range would still be very close to normal (around 10deg ) so the advantage would still apply as the penetration values only equaled out at around 30 deg. To Dave,...