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Main Archive => Navalism 3 Armed Forces => Armed Forces => New Ship Designs => Topic started by: Borys on September 11, 2007, 12:26:15 AM

Title: Somebody mentioned 18x12"?
Post by: Borys on September 11, 2007, 12:26:15 AM
A quick job - can be improved.

Enter ship name, Enter country Enter ship type laid down 1909

Displacement:
   26 354 t light; 28 035 t standard; 30 304 t normal; 32 119 t full load

Dimensions: Length overall / water x beam x draught
   665,00 ft / 665,00 ft x 96,00 ft x 28,40 ft (normal load)
   202,69 m / 202,69 m x 29,26 m  x 8,66 m

Armament:
      18 - 12,00" / 305 mm guns (6 mounts), 1 000,00lbs / 453,59kg shells, 1909 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, evenly spread, 4 raised guns
      16 - 5,00" / 127 mm guns in single mounts, 62,50lbs / 28,35kg shells, 1909 Model
     Breech loading guns in casemate mounts
     on side, all amidships
     16 guns in hull casemates - Limited use in heavy seas
      8 - 3,00" / 76,2 mm guns in single mounts, 13,50lbs / 6,12kg shells, 1909 Model
     Quick firing guns in deck mounts
     on side, evenly spread
      8 - 0,00" / 0,0 mm guns in single mounts, 0,00lbs / 0,00kg shells, 1909 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 19 108 lbs / 8 667 kg
   Shells per gun, main battery: 100
   4 - 21,0" / 533,4 mm submerged torpedo tubes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   11,0" / 279 mm   450,00 ft / 137,16 m   12,00 ft / 3,66 m
   Ends:   3,00" / 76 mm   215,00 ft / 65,53 m   10,00 ft / 3,05 m
   Upper:   7,00" / 178 mm   450,00 ft / 137,16 m   10,00 ft / 3,05 m
     Main Belt covers 104% of normal length

   - Torpedo Bulkhead:
      1,50" / 38 mm   450,00 ft / 137,16 m   30,00 ft / 9,14 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   12,0" / 305 mm   8,00" / 203 mm      11,0" / 279 mm
   2nd:   4,00" / 102 mm         -         1,00" / 25 mm
   3rd:   1,00" / 25 mm         -               -

   - Armour deck: 2,00" / 51 mm, Conning tower: 13,00" / 330 mm

Machinery:
   Coal fired boilers, steam turbines,
   Direct drive, 4 shafts, 33 923 shp / 25 307 Kw = 21,00 kts
   Range 6 000nm at 12,00 kts
   Bunker at max displacement = 4 085 tons (100% coal)

Complement:
   1 147 - 1 492

Cost:
   £2,909 million / $11,637 million

Distribution of weights at normal displacement:
   Armament: 2 083 tons, 6,9%
   Armour: 10 337 tons, 34,1%
      - Belts: 4 146 tons, 13,7%
      - Torpedo bulkhead: 749 tons, 2,5%
      - Armament: 3 467 tons, 11,4%
      - Armour Deck: 1 704 tons, 5,6%
      - Conning Tower: 272 tons, 0,9%
   Machinery: 1 696 tons, 5,6%
   Hull, fittings & equipment: 12 038 tons, 39,7%
   Fuel, ammunition & stores: 3 950 tons, 13,0%
   Miscellaneous weights: 200 tons, 0,7%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     38 321 lbs / 17 382 Kg = 44,4 x 12,0 " / 305 mm shells or 6,2 torpedoes
   Stability (Unstable if below 1.00): 1,10
   Metacentric height 5,6 ft / 1,7 m
   Roll period: 17,0 seconds
   Steadiness   - As gun platform (Average = 50 %): 59 %
         - Recoil effect (Restricted arc if above 1.00): 0,76
   Seaboat quality  (Average = 1.00): 1,25

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,585
   Length to Beam Ratio: 6,93 : 1
   'Natural speed' for length: 25,79 kts
   Power going to wave formation at top speed: 39 %
   Trim (Max stability = 0, Max steadiness = 100): 47
   Bow angle (Positive = bow angles forward): 0,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      25,00 ft / 7,62 m
      - Forecastle (20%):   18,00 ft / 5,49 m
      - Mid (50%):      17,50 ft / 5,33 m
      - Quarterdeck (15%):   17,50 ft / 5,33 m
      - Stern:      17,50 ft / 5,33 m
      - Average freeboard:   18,24 ft / 5,56 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 92,4%
      - Above water (accommodation/working, high = better): 134,7%
   Waterplane Area: 46 041 Square feet or 4 277 Square metres
   Displacement factor (Displacement / loading): 99%
   Structure weight / hull surface area: 193 lbs/sq ft or 942 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,98
      - Longitudinal: 1,20
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Good seaboat, rides out heavy weather easily

Title: Re: Somebody mentioned 18x12"?
Post by: Desertfox on September 11, 2007, 09:32:09 AM
*Starts developing Quad turrets for Agincourt...* ;D
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 09:45:00 AM
Quote from: Desertfox on September 11, 2007, 09:32:09 AM
*Starts developing Quad turrets for Agincourt...* ;D

*starts fortifing Pacific coast instalations against explosion that will occur when she's hit*
Title: Re: Somebody mentioned 18x12"?
Post by: Borys on September 11, 2007, 09:50:21 AM
Ultima Ratio Regni - Battleship laid down 1909

Displacement:
   34 814 t light; 36 866 t standard; 38 730 t normal; 40 221 t full load

Dimensions: Length overall / water x beam x draught
   676,64 ft / 665,00 ft x 110,00 ft x 29,00 ft (normal load)
   206,24 m / 202,69 m x 33,53 m  x 8,84 m

Armament:
      28 - 12,00" / 305 mm guns (7x4 guns), 864,00lbs / 391,90kg shells, 1909 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, evenly spread, 2 raised mounts
      16 - 5,00" / 127 mm guns in single mounts, 62,50lbs / 28,35kg shells, 1909 Model
     Breech loading guns in casemate mounts
     on side, all amidships
     16 guns in hull casemates - Limited use in heavy seas
      8 - 3,00" / 76,2 mm guns in single mounts, 13,50lbs / 6,12kg shells, 1909 Model
     Quick firing guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
      8 - 0,00" / 0,0 mm guns in single mounts, 0,00lbs / 0,00kg shells, 1909 Model
     Machine guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 25 300 lbs / 11 476 kg
   Shells per gun, main battery: 90

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   12,0" / 305 mm   400,00 ft / 121,92 m   15,50 ft / 4,72 m
   Ends:   4,00" / 102 mm   265,00 ft / 80,77 m   12,00 ft / 3,66 m
   Upper:   7,00" / 178 mm   400,00 ft / 121,92 m   10,00 ft / 3,05 m
     Main Belt covers 93% of normal length

   - Torpedo Bulkhead:
      4,00" / 102 mm   380,00 ft / 115,82 m   25,00 ft / 7,62 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   12,0" / 305 mm   9,50" / 241 mm      11,0" / 279 mm
   2nd:   4,00" / 102 mm   2,00" / 51 mm      2,00" / 51 mm

   - Armour deck: 3,00" / 76 mm, Conning tower: 15,00" / 381 mm

Machinery:
   Coal fired boilers, steam turbines,
   Direct drive, 4 shafts, 33 989 shp / 25 356 Kw = 20,00 kts
   Range 6 000nm at 10,00 kts
   Bunker at max displacement = 3 356 tons (100% coal)

Complement:
   1 379 - 1 794

Cost:
   £4,113 million / $16,452 million

Distribution of weights at normal displacement:
   Armament: 3 163 tons, 8,2%
   Armour: 14 618 tons, 37,7%
      - Belts: 5 081 tons, 13,1%
      - Torpedo bulkhead: 1 406 tons, 3,6%
      - Armament: 4 683 tons, 12,1%
      - Armour Deck: 3 079 tons, 7,9%
      - Conning Tower: 370 tons, 1,0%
   Machinery: 1 699 tons, 4,4%
   Hull, fittings & equipment: 15 280 tons, 39,5%
   Fuel, ammunition & stores: 3 916 tons, 10,1%
   Miscellaneous weights: 54 tons, 0,1%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     47 667 lbs / 21 621 Kg = 55,2 x 12,0 " / 305 mm shells or 8,3 torpedoes
   Stability (Unstable if below 1.00): 1,10
   Metacentric height 6,9 ft / 2,1 m
   Roll period: 17,6 seconds
   Steadiness   - As gun platform (Average = 50 %): 60 %
         - Recoil effect (Restricted arc if above 1.00): 0,69
   Seaboat quality  (Average = 1.00): 1,23

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,639
   Length to Beam Ratio: 6,05 : 1
   'Natural speed' for length: 25,79 kts
   Power going to wave formation at top speed: 39 %
   Trim (Max stability = 0, Max steadiness = 100): 49
   Bow angle (Positive = bow angles forward): 17,00 degrees
   Stern overhang: 4,00 ft / 1,22 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      25,00 ft / 7,62 m
      - Forecastle (21%):   19,00 ft / 5,79 m
      - Mid (50%):      19,00 ft / 5,79 m
      - Quarterdeck (22%):   19,00 ft / 5,79 m
      - Stern:      19,00 ft / 5,79 m
      - Average freeboard:   19,50 ft / 5,94 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 92,1%
      - Above water (accommodation/working, high = better): 145,6%
   Waterplane Area: 55 473 Square feet or 5 154 Square metres
   Displacement factor (Displacement / loading): 89%
   Structure weight / hull surface area: 213 lbs/sq ft or 1 038 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,97
      - Longitudinal: 1,23
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Good seaboat, rides out heavy weather easily

Title: Re: Somebody mentioned 18x12"?
Post by: maddox on September 11, 2007, 10:07:39 AM
Reminds me of my mongrel.

USS Agincourt with French 15" quads. But that's WW II style
Title: Re: Somebody mentioned 18x12"?
Post by: Tanthalas on September 11, 2007, 11:42:36 AM
atm i dont think any of us could build that... quads
Title: Re: Somebody mentioned 18x12"?
Post by: Borys on September 11, 2007, 11:55:03 AM
1914 quad turrets, turreted secondaries, improved Torpedo Protection

Just over the horizon ...
Title: Re: Somebody mentioned 18x12"?
Post by: Tanthalas on September 11, 2007, 11:56:24 AM
which lends itself to hmmmmm, thats the next gun step for me i wonder.
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 12:08:05 PM
That's definately one of those things that make you go "Hmmmmm."
Wonder what I can do with something like that.
Oh well, can't find out on the school comps... they don't have .net on them, so I can't run SpringSharp here. Also, being a non-techie type, I have difficulty with Springstyle. :(
Title: Re: Somebody mentioned 18x12"?
Post by: Ithekro on September 11, 2007, 12:40:46 PM
Quads are a tricky thing.  The 1914 quads are those for the Normandy-class French Battleships historically.  I don't think any of the actual turrets were completed and I don't know if the system was tested ever.  After that we wait until about 1930s for the next French capital ships armed with quad turrets and finally the King George V-class battleships from the United Kingdom in the late 1930s.  (and plans for quad 14" turrets for the first American Fast Battleships before the go ahead for 16" guns came through).

Worse are the plans for sextuple turrets on an American design in the 1910s.
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 12:51:01 PM
Well, as I understand it, none of the early 'quads' were actually 'quads'... they were 'double twins.'
They simply had the machinery from two twin turrets sitting side-by-side.
That shouldn't be too hard to pull off at all, it seems.
Title: Re: Somebody mentioned 18x12"?
Post by: The Rock Doctor on September 11, 2007, 12:53:06 PM
QuoteWorse are the plans for sextuple turrets on an American design in the 1910s.

Ah yes, gatlings.
Title: Re: Somebody mentioned 18x12"?
Post by: Borys on September 11, 2007, 12:54:40 PM
Ahoj!
The "double twins" is true of the French quads - IIRC the 1914 variety, and doubtlessly the 13 and 15 inchers from the 1930s.
The British guns were IIRC "genuine" quads.

Borys
Title: Re: Somebody mentioned 18x12"?
Post by: Tanthalas on September 11, 2007, 12:59:22 PM
i tend to feal that tripples are plenty to deal with.  Just look at the trouble im having with my 4x3 ship lol
Title: Re: Somebody mentioned 18x12"?
Post by: Ithekro on September 11, 2007, 01:11:41 PM
Heh, actually a gatling style 12" cannon might be amusing to design....or as they say nearly impossibel and impractical.  But the sextuple turret looked impracticle to begin with (pobably was going to be a set of paired triple mounts in one turret like the French paired twin mounts as a quad).  When I heard of it the first time (I think it was a Tillman type) I was thinking stacked triple turrets like the Virginia class predreadnoughts has with their stacked twin 12"/8" combo.
Title: Re: Somebody mentioned 18x12"?
Post by: Desertfox on September 11, 2007, 01:35:18 PM
Agincourt with Stacked Sextuples? :o Now that   I have to build. ;D

A Gatling 6" Cannon might be more pausible and just as interesting, considering the troubles Ive had with DDs NS might just try to develop a smaller 4" Gatling.
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 03:24:37 PM
Quote from: Borys on September 11, 2007, 12:54:40 PM
The British guns were IIRC "genuine" quads.

That's why I specified the 'early' part.
I knew the 4x14" gunhouses proposed for the N.C. class were 'true' quads, and I thought the same was true for the ones on the KGV's were as well.
Title: Re: Somebody mentioned 18x12"?
Post by: Borys on September 11, 2007, 03:34:34 PM
Ahoj!
I got mixed up, as the French stuck to the double twin concept.
Borys
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 03:50:35 PM
Quote from: Desertfox on September 11, 2007, 01:35:18 PM
Agincourt with Stacked Sextuples? :o Now that   I have to build. ;D

A Gatling 6" Cannon might be more pausible and just as interesting, considering the troubles Ive had with DDs NS might just try to develop a smaller 4" Gatling.

Maybe by the late 40's or early 50's... till then, about 2" would be the top end on a gatling-type gun- anything bigger would fire rounds faster than they could be loaded.
Title: Re: Somebody mentioned 18x12"?
Post by: Korpen on September 11, 2007, 03:59:45 PM
Quote from: Carthaginian on September 11, 2007, 03:50:35 PM
Quote from: Desertfox on September 11, 2007, 01:35:18 PM
Agincourt with Stacked Sextuples? :o Now that   I have to build. ;D

A Gatling 6" Cannon might be more pausible and just as interesting, considering the troubles Ive had with DDs NS might just try to develop a smaller 4" Gatling.

Maybe by the late 40's or early 50's... till then, about 2" would be the top end on a gatling-type gun- anything bigger would fire rounds faster than they could be loaded.
A more interesting question would be why anyone would want a gattling at all? It does not have any real advantage over a more conventional gun or revolver cannon, and it weights considerably more.
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 04:15:59 PM
Quote from: Korpen on September 11, 2007, 03:59:45 PM
A more interesting question would be why anyone would want a gattling at all? It does not have any real advantage over a more conventional gun or revolver cannon, and it weights considerably more.

Well, for small caliber gatlings, there is one ENORMOUS advantage... barrel temperature.
The fact that multiple barrels are firing the projectiles means that the heat is not concentrated in one location. The guns can fire for much longer periods of time without damaging the barrels.

For something this large, however, that advantage is a moot point.
You simply can't load anything bigger than a 1"/25mm fast enough to overheat the barrels.
Title: Re: Somebody mentioned 18x12"?
Post by: Korpen on September 11, 2007, 04:24:40 PM
Quote from: Carthaginian on September 11, 2007, 04:15:59 PM
Well, for small caliber gatlings, there is one ENORMOUS advantage... barrel temperature.
The fact that multiple barrels are firing the projectiles means that the heat is not concentrated in one location. The guns can fire for much longer periods of time without damaging the barrels.

For something this large, however, that advantage is a moot point.
You simply can't load anything bigger than a 1"/25mm fast enough to overheat the barrels.
Oh, it is perfectly possible to overheat larger barrels, that is often one factor that limits the sustained ROF for field artillery even today.
And pretty much all automatic cannons could risk overheating, but the easiest way to reduce the risk for that was to add extra cooling to the gun. That is why pretty much all automatic canons have been water cooled in situations were weight was no major concern.
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 04:54:54 PM
Quote from: Korpen on September 11, 2007, 04:24:40 PM
Oh, it is perfectly possible to overheat larger barrels, that is often one factor that limits the sustained ROF for field artillery even today.

Emphasis mine... and that's my point.
You have to fire a large-caliber artillery piece VERY rapidly for a fairly long time to overheat it... like a ROF that couldn't be sustained at the time this discussion is taking place in N-verse. ;)

Quote from: Korpen on September 11, 2007, 04:24:40 PM
And pretty much all automatic cannons could risk overheating, but the easiest way to reduce the risk for that was to add extra cooling to the gun. That is why pretty much all automatic canons have been water cooled in situations were weight was no major concern.

Well, I've never seen a 105mm that was water cooled. ;)
Those take- according to my grandfather- quarter of an hour or more at max ROF to really start getting too hot to fire without destroying the barrel. Of course, he's relying on 60 year old data.
Title: Re: Somebody mentioned 18x12"?
Post by: Ithekro on September 11, 2007, 04:59:35 PM
For a truely sick rapid fire cannon you need the American 8"/55 cal Mark 16 of the Des Moines-class heavy Cruisers with a fire rate of 10 shells per minute per barrel.  But you need to wait until the mid-late 1940s.
Title: Re: Somebody mentioned 18x12"?
Post by: Korpen on September 11, 2007, 05:05:03 PM
Quote from: Carthaginian on September 11, 2007, 04:54:54 PM
Quote from: Korpen on September 11, 2007, 04:24:40 PM
Oh, it is perfectly possible to overheat larger barrels, that is often one factor that limits the sustained ROF for field artillery even today.

Emphasis mine... and that's my point.
You have to fire a large-caliber artillery piece VERY rapidly for a fairly long time to overheat it... like a ROF that couldn't be sustained at the time this discussion is taking place in N-verse. ;)
Not that extreme, for a 15cm guns 3-4 RPM is the maximum sustained fire today. However a modern gun can fire 20+ round in less then two minutes without any problems, but not for extended periods.

Quote
Quote from: Korpen on September 11, 2007, 04:24:40 PM
And pretty much all automatic cannons could risk overheating, but the easiest way to reduce the risk for that was to add extra cooling to the gun. That is why pretty much all automatic canons have been water cooled in situations were weight was no major concern.

Well, I've never seen a 105mm that was water cooled. ;)
Those take- according to my grandfather- quarter of an hour or more at max ROF to really start getting too hot to fire without destroying the barrel. Of course, he's relying on 60 year old data.
'
That might have something to do with the fact that army guns are subject to weight concerns, naval guns are not (to the same degree).
And how many 12cm guns with a ROF of over 80rpm have you seen? ;)
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 05:29:59 PM
Man, I don't know if the WORLD has ever seen a 105mm that could fire 80 RPM!
That's, like, a round every .6 seconds.
Most semi-auto rifles can't do that unless they are in very skilled hands.
Title: Re: Somebody mentioned 18x12"?
Post by: P3D on September 11, 2007, 05:33:47 PM
A 6-barrel gatling cannon IMO would have lower ROF than a six-barrel mount...

For 155mm, the sustained ROF is 2/min (1950-60-era systems do 1/2min). It can be overcome by
a/ water cooling (AGS, Crusader)
b/ twin-barrel (Russian Koalitsiya SPH)
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 06:54:37 PM
Quote from: P3D on September 11, 2007, 05:33:47 PM
A 6-barrel gatling cannon IMO would have lower ROF than a six-barrel mount...

The only problem with larger mounts comes in keeping them in ammo.
That is the practical limitation; if the ammo could be fed fast enough, the multi-barrel design would always win out.
Title: Re: Somebody mentioned 18x12"?
Post by: johnestauffer on September 11, 2007, 07:31:26 PM
Beyond a certain point it seems the number of barrels per platform becomes a losing proposition.
While you can put double/triple the number of barrels on a single ship, you now have a heavily armed ship that is extremely vulnerable.  With more platforms you make the opponents targeting more difficult and reduce the opportunity for a hit that places your single, overarmed platform out of combat.
Plus, a single ship can only be in a single place. If you spread the firepower over multiple platforms you can deploy your forces more effectively.

But it is an interesting exercise.
The Agincourt worked out ok in the RN, given the large number of other capital ships.
But could the same be said in a small navy, where 18 guns were concentrated in a single ship?
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 11, 2007, 07:36:56 PM
Quote from: johnestauffer on September 11, 2007, 07:31:26 PM
The Agincourt worked out ok in the RN, given the large number of other capital ships.
But could the same be said in a small navy, where 18 guns were concentrated in a single ship?

This would depend:
1.) are you far superior to the navy you are building to impress?
2.) are you building this ship in response to a similar ship buitl by another navy?

Both of those situations would necessitate- at least from a 'national pride' standpoint, the building of such a ship.
Otherwise, it's too many eggs in one basket.
Title: Re: Somebody mentioned 18x12"?
Post by: Korpen on September 11, 2007, 11:11:23 PM
Quote from: Carthaginian on September 11, 2007, 05:29:59 PM
Man, I don't know if the WORLD has ever seen a 105mm that could fire 80 RPM!
That's, like, a round every .6 seconds.
Most semi-auto rifles can't do that unless they are in very skilled hands.
First i would like to point out that a 12cm automatic canon is a tiny bit too large to be hand-held, no matter how skilled hands. ;)

And then I give you: http://www.navweaps.com/Weapons/WNSweden_47-46_TAK120.htm
12cm, 80 RPM.
If you are looking for a 10cm with that kind of ROF there is always the French: http://www.navweaps.com/Weapons/WNFR_39-55_m1968.htm
Title: Re: Somebody mentioned 18x12"?
Post by: Borys on September 12, 2007, 12:54:52 AM
Ahoj!
AFAIK current 5 inch or so ship mounted guns are often water cooled. They are automatic, and can fire 10-12 rounds per minute. They can fore at this rate for a minute or two, and then have to cool down. Of they fre at a lesser rate for a longer period. Water cooling allows them to fire for longer

SP land 6 inch or s howitzers with automatic feed have similar capability. Here the idea is to fire of half a dozen rounds and scoot. The theorietical ROF of c.8-10 per minute cannot be sustained for over a minute due to heat.

http://www.navweaps.com/Weapons/WNRussian_51-70_ak130.htm

I do not believe in 40 rpm - maybe the mechanism could take it, but I doubt if the barrels can. What they can do is fire bursts - 4 shells in 6 seconds - then wait for a dozen seconds or so - then fire again. They still will overheat, but after 2 or 3 minutes, not withing 20 seconds.
That's how I understood this stuff, so I could be wrong.

A thing to be noted about the guns Korpen mentioned - they have ready use magazines which they can fire off in 20-30 seconds at full theoretical ROF.
THAT keeps them from overheating :)

Just like with a machine gun - after how many minutes of continuous fire, with no barrel swaps, will a MaDuece fail?

So it is a yes and no answer.
Yes, 6 inch guns can fire at 10 rounds a minute (or more).
No, they cannot do it for very long - such a ROF is counted in tens of seconds.

Borys
Title: Re: Somebody mentioned 18x12"?
Post by: P3D on September 12, 2007, 12:59:46 AM
There are no fielded fully automatic self-propelled artillery systems. The Germans, US and Russia has prototypes.
Title: Re: Somebody mentioned 18x12"?
Post by: Korpen on September 12, 2007, 01:23:09 AM
Quote from: P3D on September 12, 2007, 12:59:46 AM
There are no fielded fully automatic self-propelled artillery systems. The Germans, US and Russia has prototypes.
That is incorrect: Bandkanon 1C
Full automatic feed, 14 rounds in 45 seconds. http://en.wikipedia.org/wiki/Bandkanon_1

Then you got a bunch of guns such as the FH-77 were the gun is automatically loaded from a loading tray, allowing it to fire a three round burst in about 8-10 sec.
And this is guns that is more the 30 years old...
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 12, 2007, 07:26:05 AM
Korpen,

These guns illustrate my point.
They may have a THEORETICAL cyclic of 80 RPM, but this cannot be achieved due to ammunition feed problems. Something that big just cannot be fed fast enough... heck, it's rough to keep a standard M2 .50 caliber fed to a point you can achieve it's full cyclic rate. To do that, you have to join belts prior to beginning your test, and THEN have to have 2 or 3 guys watching the belt to make sure there are no kinks, snags, or bad joints in the belts. On top of THAT, you have to be aware that the M2 is a closed-bolt weapon, and that if you get things too hot, you'll start getting cook-off's and mis-feeds.
Title: Re: Somebody mentioned 18x12"?
Post by: Korpen on September 12, 2007, 07:52:09 AM
Quote from: Carthaginian on September 12, 2007, 07:26:05 AM
Korpen,

These guns illustrate my point.
They may have a THEORETICAL cyclic of 80 RPM, but this cannot be achieved due to ammunition feed problems. Something that big just cannot be fed fast enough... heck, it's rough to keep a standard M2 .50 caliber fed to a point you can achieve it's full cyclic rate. To do that, you have to join belts prior to beginning your test, and THEN have to have 2 or 3 guys watching the belt to make sure there are no kinks, snags, or bad joints in the belts. On top of THAT, you have to be aware that the M2 is a closed-bolt weapon, and that if you get things too hot, you'll start getting cook-off's and mis-feeds.
That applies to ALL automatic weapons, so far I have never heard about any weapon whose cyclic rate of fire is the same as its practical rate of fire.

However as the AA version of the 12cm TAK had 48 ready round, and had not problem firing them in one volley, them main reason larger magazines were not used was that the naval gun was intended for very light crafts.
Sure no matter witch gun you use sooner or later you will risk overheating, but it is a very minor problem compared to keeping the gun fed. :)
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 12, 2007, 08:01:17 AM
Quote from: Korpen on September 12, 2007, 07:52:09 AM
That applies to ALL automatic weapons, so far I have never heard about any weapon whose cyclic rate of fire is the same as its practical rate of fire.

Well, I HAVE come pretty close on an FN SAW.
It took 4 belts and a really good loader, but we burned about 650 rounds in a minute, on a weapon that had a cyclic of 800 RPM.

Of course, that was a few weeks before we got new barrels for our SAWs... we showed that barrel to the inspectors. Sometimes you gotta get creative to get new equipment. :D
Title: Re: Somebody mentioned 18x12"?
Post by: P3D on September 12, 2007, 02:58:24 PM
Reminds me some Hungarian AK clone (AMD) where the barrel was made of cheap material, and would erode fast on full auto...
The other Hungarian AK clone had no such problems IIRC.
Title: Re: Somebody mentioned 18x12"?
Post by: Carthaginian on September 12, 2007, 03:56:49 PM
Well, those have problems 'new in box.'
This weapon's barrel was at least 5 years and 1200 rounds old, and was starting to get rust spots. We just wanted something new ans shiny, so we did what the owner's manual said not to do. ;)
Title: Re: Somebody mentioned 18x12"?
Post by: swamphen on September 14, 2007, 07:50:41 PM
Quote from: Carthaginian on September 12, 2007, 03:56:49 PM
Well, those have problems 'new in box.'
This weapon's barrel was at least 5 years and 1200 rounds old, and was starting to get rust spots. We just wanted something new ans shiny, so we did what the owner's manual said not to do. ;)

I.E., ignored the 'don't try this at home kids' label?  :P


Meanwhile:
*looks at Swiss "Agincourt", parked in Anchorage harbour, other end of ocean from Brandenburg*
*sees fuse burning on Swiss ship's centre magazine*
*dives into Brandenburgian foxhole and prays*
:D

Title: Re: Somebody mentioned 18x12"?
Post by: P3D on September 15, 2007, 12:43:05 PM
Quote from: Korpen on September 12, 2007, 01:23:09 AM
Quote from: P3D on September 12, 2007, 12:59:46 AM
There are no fielded fully automatic self-propelled artillery systems. The Germans, US and Russia has prototypes.
That is incorrect: Bandkanon 1C
Full automatic feed, 14 rounds in 45 seconds. http://en.wikipedia.org/wiki/Bandkanon_1

Then you got a bunch of guns such as the FH-77 were the gun is automatically loaded from a loading tray, allowing it to fire a three round burst in about 8-10 sec.
And this is guns that is more the 30 years old...

True. However, Bandkanon uses fixed ammo, and has very limited flexibility compared to 5-6 zone charges. It is rather an MRLS/Katyusha-like area saturation weapon than modern SP Artillery that can do MRSI.
FH-77 is using special ammunition to reach that ROF, with NATO bagged charges ROF  is lower, and its flexibility is also limited. The export variant FH-77B has slightly lower ROF, but still higher than hand-loaded contemporaries (3 rounds in 10 vs 15s).
Title: Re: Somebody mentioned 18x12"?
Post by: Korpen on September 15, 2007, 02:01:08 PM
Quote from: P3D on September 15, 2007, 12:43:05 PM
Quote from: Korpen on September 12, 2007, 01:23:09 AM
Quote from: P3D on September 12, 2007, 12:59:46 AM
There are no fielded fully automatic self-propelled artillery systems. The Germans, US and Russia has prototypes.
That is incorrect: Bandkanon 1C
Full automatic feed, 14 rounds in 45 seconds. http://en.wikipedia.org/wiki/Bandkanon_1

Then you got a bunch of guns such as the FH-77 were the gun is automatically loaded from a loading tray, allowing it to fire a three round burst in about 8-10 sec.
And this is guns that is more the 30 years old...

True. However, Bandkanon uses fixed ammo, and has very limited flexibility compared to 5-6 zone charges. It is rather an MRLS/Katyusha-like area saturation weapon than modern SP Artillery that can do MRSI.
FH-77 is using special ammunition to reach that ROF, with NATO bagged charges ROF  is lower, and its flexibility is also limited. The export variant FH-77B has slightly lower ROF, but still higher than hand-loaded contemporaries (3 rounds in 10 vs 15s).
Bertil is in fact a quite different gun from Adam, as it got an ogival screw breech, rather then the sliding breach block in 77A.
I think it is wrong to call the ammunition to 77A "special", as the only special thing about it was that it was not a NATO standard case, and at the time there was no reason to take that into account.

BKan had its drawbacks, nobody is denying that, but it was excellent at the work it did.
It did sever in the 2nd & 6th fördelningskanonbattaljonerna (divisional artillery battalions) in northern Sweden, and it main work was interdiction against a (soviet) invader. For this work, it very high ROF, long range (~26km) and good accuracy counted for much more then its inflexibility. As a side note, It could do MRSI. :)

By its nature rocket artillery require a larger weight of munitions to engage a target then conventional artillery. This means that while it is always cost-efficient to engage with shells, with rockets that is not the case.
MRSI is not something magical, it simply a usage of the fact that the effect of barrage is cut in half in 15sec again personnel.
Rocket artillery have its use, but so does the superior accuracy, cost-efficiency and readiness of conventional guns.