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check this out:
At 19.12 hours on 25 Aug, 1940, the unescorted Jamaica Pioneer (Master Thomas Elwyn Maurice Jenkins) was hit by a torpedo from U-100 east of Rockall. The ship had been missed by another torpedo at 19.08 hours and was missed again at 19.30 hours. After a second hit at 19.34 hours, the U-boat tried to sink the vessel by gunfire and fired 55 rounds without hitting the ship, which was finally sunk with a coup de grâce at 20.12 hours. Two crew members were lost. The master, 52 crew members and two gunners were rescued. Some of them were picked up by the British destroyer HMS Anthony (H 40) (LtCdr N.J.V. Threw) and landed at Greenock and the remaining survivors by the British destroyer HMS Wanderer (D 74) (Cdr J.H. Ruck-Keene) and were landed at Belfast.
man they must have some ubernerfing rub mod installed. [/b]
Gizzmoe
08-25-05, 01:02 PM
fired 55 rounds without hitting the ship
Not bad! :lol: It´s also interesting to read that three torpedos were needed to sink it...
Some informations about the ship:
JAMAICA PIONEER(1931)
ss JAMAICA PIONEER
built by Lithgows Port Glasgow,
Yard No 851
Port of Registry: London
Propulsion: Steam quad expansion.
Built: 1931
Ship Type: Refrigerated Cargo Vessel
Tonnage: 5349 grt
Owner History:
Kaye Son & Co. London
Status: Torpedoed & Sunk - 25/08/1940
After a second hit at 19.34 hours, the U-boat tried to sink the vessel by gunfire and fired 55 rounds without hitting the ship, which was finally sunk with a coup de grâce at 20.12 hours.
55 rounds in approximatly 30 minutes... so thats... about 2 rounds a minute? Not a bad firing rate.
Drebbel
08-25-05, 01:56 PM
After a second hit at 19.34 hours, the U-boat tried to sink the vessel by gunfire and fired 55 rounds without hitting the ship, which was finally sunk with a coup de grâce at 20.12 hours.
55 rounds in approximatly 30 minutes... so thats... about 2 rounds a minute? Not a bad firing rate.
Looks like they concentrated on reloading instead of aiming :D
SmokinTep
08-25-05, 03:03 PM
:rotfl: :rotfl:
Ula Jolly
08-25-05, 03:22 PM
Wh.. did they use the chef to aim or something? :dead:
cunnutazzo
08-25-05, 03:30 PM
Is it possible to know the weather conditions and other of this mission? I think that some crews were better than the other.
Wh.. did they use the chef to aim or something? :dead:
U-boat crews were notoriously poor shots. It's not like they got much practice after all, and when they could use the deck gun it was usually just to finish off a ship, so they could get in close. The biggest problems with the game's deck gun are that it has a fantasy stabilization system along the lines of that fitted to a modern day Main Battle Tank, and the AI deck gun crew are about 10 times more accurate than any real crew.
Ha! I was right. 30 seconds for reload a shell. :roll: I wish people could learn to listern to a more sensual and practical opinion.
JayW,
Ha! I was right. 30 seconds for reload a shell. :roll: I wish people could learn to listern to a more sensual and practical opinion.
JayW,
I agree with the fact that reload should take 36 Seconds (Give or take a few seconds depending on variables) BUT I also agree that SH3 uses too few shells to sink a ship.
From my Experience with Rub 1.42 Im happy to leave the Deck gun as Beery has made it - It fires slow but I believe it represents a realistic amount of damage per unit time overall, which is what REALLY matters.
I have used it on a 2500 Ton small merchant which took 1HR and 33 Rounds to Sink - The 1Hour time frame to me seems more than fair.
Ha! I was right. 30 seconds for reload a shell. :roll: I wish people could learn to listern to a more sensual and practical opinion.
JayW,
30 seconds for an average reload would be fine IF the U-boat only carried 50 or 60 shells, but U-boats carried something like 200 shells. If that boat had fired more of its ammo the average reload rate would go down rapidly (because the first 20 shells skew the average). I don't see why that's so difficult for some people to understand. The above example of 36 seconds per reload fits perfectly within what should be expected for the reload rate when you only consider the first 50 or 60 shells. The problem is, you cannot restrict players to only firing 50 or 60 shells per engagement. I'd be more than happy to bring up the reload rate to 30 seconds if players were willing to carry only 60 shells on their U-boat. Somehow I doubt that pro-fast-reload players would go for that, probably because they know darned well that they routinely fire a heck of a lot more shells in an engagement.
The Ready Ammo Locker is the Biggest variable there is that will scew figures as in most cases we never know how FULL it was when the Uboat started shelling.
I have an Interesting example from the book: "Hirschfeld - The secret diary of a U-Boat"
Pages 127 &&- 129
U-109 Type IXB Gun 10.5CM 5TH Patrol
On 6th Feb 1942 he sank the Panamanian 3,531 ton Halcyon.
Which was the 4th and last ship sunk on this Patrol but the first that had seen action from the Deck gun.
From this we can conclude all 32 Rounds were in the Ready ammunition locker on Deck.
NB: I got the Figure of 32 from here- it appears the TYPEIX's had a larger ready ammo container then the TYPE VII's: http://www.uboatarchive.net/U-185INT.htm
U-185 was a TYPE IXC
The 3,531 ton Halcyon was in balast and was sunk by Deck gun ALONE as all torpedos had missed prior to that.
QUOTE: " It was exactly 01:30 when the Commander gave the order to fire. The boat trembled as the first 10.5cm shell howled away..................An hour after we had opened fire we had let her have 100 rounds but the steamer was still afloat.The ship appeard deserted and drifting in the heavy seaway, her entire stern section in flames. It fell quiet as we closed in. At a range of 400 yards Bleichrodt told Maureschat to resume the shelling.............Bleichrodt read the signal and said 'Damn, she's still not sinking,'then shouted down to Maureschat, 'How many rounds have you got left?'
'Twenty Captain.'
'Get ready , Maureschat. Im going to get in really close and I want you to give her a final battering.'Bleichrodt called out to the stern, 'Berthold,Im going in close.Keep shooting at her waterline.'......................Abeam on either side she had a gaping hole large enough to drive a bus through, but she still wouldnt go down...........It was now daylight and we all gazed at the burning derelict nearby. Bleichrodt said to me, 'we'll have to leave now, the boys from burmuda will be here soon.'.............................just as he was about to go, a voice on the bridge shouted, 'Steamers sinking by the stern!'. 'Thank god for that' said Maureschat. 'Now I can get some sleep' We had expended 200 10.5cm and 100 3.7cm shells in the effort to sink the Halcyon." END QUOTE
From the above we gain a few pieces of information.
1) In 1 Hour the crew of U-109 were able to fire a total of 100 Rounds from the 10.5cm deck gun.
2) It took 200 10.5cm rounds of ammunition not to mention 100 3.7cm rounds to bring the Halcyon a 3,500 Ton ship in ballast to its knees.
3) Approx 100 10.5 cm rounds were fired within 400 Yards range.
Additional notes:
German 10.5 cm/45 (4.1") SK C/32 - Complete HE Round weight = 53.35 lbs. (24.2 kg).
German 8.8 cm/45 (3.46") SK C/35 - Complete HE Round Weight = HE - 33 lbs. (15 kg).
Above information provided from http://www.navweaps.com
From the information provided the Type IX had a ready ammo locker some 60% greater storage capacity than a type VII and a Total HE Round weight 2.68 times greater than a TYPE VII.
Calculations:
100 RPH (Rounds Per Hour) for a TYPE IX Crew.
32 Rounds from Ready Ammo Locker.
MAXIMUM Fireing Rate of Weapon 15 RPM (Rounds Per Minute).
According to Hirshfeld the gun crew of U-109 were able to hoist 68 *24.2KG shells in 1 Hour to be fired. IE: 100-32 = 68
Which equals 53 Seconds per round or 1645.6KG per Hour.
NB: According to Hirshfeld the Ammo from the Magazine was being hoisted the very second the 10.5cm gun began fireing.
According to http://www.uboatarchive.net/U-128INT.htm
The following gun crew was used on a TYPE IX
"The crew necessary to man the gun totals usually 13 men. The second watch officer is in charge of all gunnery aboard. A petty officer is the gun captain and Number One man. Number Two man is the gun pointer; Number Three operates the breech mechanism, number four fires the gun. Numbers five and Six are called “Ladenummer”, and they load the gun. The rest of the gun crew passes ammunition from the ammunition locker in the control room up the conning tower and onto the deck. No ammunition hoist is provided."
This provides us with 7 men below deck feeding ammunition from the Magazine through Zentrale and up the conning tower.
It appears out of the 13 Man gun crew a total of 9 actually handle the ammunition on its way from the magazine to the gun breech.
53 seconds divided by 9 men requires that each man on average is expected to be in posession of a shell every 6 seconds.
While a Type VII Shell is much lighter shaving more than a second off 6 seconds per man would probably be highly unlikely as the movement of the shell is still restricted by the rate it can be passed along the human chain.
If we apply the above to a TYPE VII with 20 Rounds in the Ready ammo locker with a Rate of 5 seconds per shell per man we get:
5*9=45 which is 80 shells per Hour or 1200KG per Hour.
In both cases we get 100 Rounds per Hour
The second hour would see a drop in Shell rate due to two factors
1) We have used all the ready ammo store.
2) The gun crew is not as fresh as when it commenced.
Some good info there, but I see a few problems with it:
Firstly, a piece of info is missing: how long does it take to prepare the gun from the order being given until the first shot is fired? This must be included as part of any realistic reload simulation.
Secondly, if the maximum RPM is 15, that's 1 round every 4 seconds. That rate of fire is equal to the speed that a well-trained British WW1 infantryman could load, aim and fire a magazine-fed Short Magazine Lee-Enfield Rifle. I simply cannot believe that a non-clip-fed shell weighing 53lbs could be carried from a deck mounted box, loaded, aimed on a pitching and rolling deck and fired as fast as a soldier could load, aim (on dry land) and fire a magazine-fed rifle round weighing a couple of ounces. Such a feat strains credulity well beyond the limit, especially when you consider that in most U-boats the ready use ammunition locker was located nearly 12 feet away from the breech. Surely this 15RPM is the absolute maximum ROF with ammo ready AT THE GUN and not taking into account aiming. That is the only way I can see getting 15 RPM out of this gun. Such a ROF is far faster than the rate of fire that could be achieved in combat conditions.
Thirdly, the 'an hour after we had opened fire' doesn't seem as precise in the wording as the 'It was exactly 01:30' bit. Plus, when the hour is up, apparently there are only 20 rounds left. According to the quote, the boat fired 200 shells into her. What happened to the other 80 shells? No mention at all is made of them.
Also, U-185 was not a Type IXC. She was in fact a Type IXC-40. I have no idea whether the IXC-40 carried the same ready use ammo capacity as the Type IXB, but according to your source (http://www.uboatarchive.net/U-185INT.htm) U-185 only carried 60 105mm rounds - a lot less than the 200 apparently carried on board U-109. Not that this has direct bearing on the matter, but if the ammo loadouts were that different, maybe other aspects of ammunition use were too.
Finally, it is clear that both 105mm and 37mm shells were fired. But no mention is made of when the 37mm shells were fired. Could it have been combined fire that made up the 100 rounds? It does not state clearly what sort of ammo made up the 100 rounds.
In short, there is too much left out of the report. We can't calculate anything from this.
In my opinion, the rate of fire reported would be physically impossible for a single 105mm gun. I just do not see how any crew could possibly get a 53lb shell out of a sunken container, across 12ft of deck to the loader, then load it into the breech, wait for the boat to pitch and roll up or down to the desired aim position, and fire, all in 4 seconds. I realise that gun crews are efficient but, as far as I can see, it would take nearly 4 seconds just to lift the 53lb shell out of the box. I can buy the 53 seconds for the rounds hoisted from below, but there's something very fishy about the rate of fire for the rest of the ammo.
It's well-researched info, but somehow I doubt the sources, or there is some essential info missing. Plus, I'm certain that some of the source material relates to firing the gun in perfect conditions - conditions that do not relate in any way to combat. If the report is accurate about the '1 hour' thing, I would hazard a guess that the '100 rounds' fired into her over the course of an hour included a good few 37mm shells.
Catfish
08-27-05, 03:46 AM
Hello,
well, i read about Topp that he threatened to sink a merchant during storm and big waves with a torpedo, but they did not really have one left. He signalled to leave the ship, and the frightened enemy crew obeyed. After the crew had left the steamer Topp ordered to blow the tanks more than once with the Diesel exhaust gases to get his boat out of the water as much as possible, waves still flooding the boat's deck. The crew then began to shell the steamer which sunk after an hour and 90 shots (i think it was a VIIC boat with the naval 8,8 C35 gun). The smaller gun mentioned in the posting above will have been used to shoot venting holes into the steamer's hatch covers in order to speed up the sinking, a usual procedure.
What i want to say is we get information from various reports, but you simply cannot generalize that a steamer of XYZ tons sinks after exactly 10 shots taking two minutes. It depends on the crew, sea state (not only because the gun will be difficult to aim, but also as soon as there's a gaping hole in the hull, big waves will sink a ship faster than in calm seas), the ballast or loading of the ship, whether it is ammunition or iron (or wood). So there is a lot of chance inherent on what will happen.
I think the current modelling of the Rub 1.43 is over all the best solution. I sank a 3000 ton ship in 5 minutes as well as another one in more than an hour - some variability is perfect here.
Greetings,
Catfish
Some good info there, but I see a few problems with it:
Firstly, a piece of info is missing: how long does it take to prepare the gun from the order being given until the first shot is fired? This must be included as part of any realistic reload simulation.
I agree, this time would need to be included as would any time required to bring up the sights from the conning tower which were never left on the gun itself during operations.
Secondly, if the maximum RPM is 15, that's 1 round every 4 seconds. That rate of fire is equal to the speed that a well-trained British WW1 infantryman could load, aim and fire a magazine-fed Short Magazine Lee-Enfield Rifle. I simply cannot believe that a non-clip-fed shell weighing 53lbs could be carried from a deck mounted box, loaded, aimed on a pitching and rolling deck and fired as fast as a soldier could load, aim (on dry land) and fire a magazine-fed rifle round weighing a couple of ounces. Such a feat strains credulity well beyond the limit, especially when you consider that in most U-boats the ready use ammunition locker was located nearly 12 feet away from the breech. Surely this 15RPM is the absolute maximum ROF with ammo ready AT THE GUN and not taking into account aiming. That is the only way I can see getting 15 RPM out of this gun. Such a ROF is far faster than the rate of fire that could be achieved in combat conditions.
Im not shore how anyone could think for a second that the ROF of 15 RPM could be remotely considered as a Real operational figure which it clearly is not. This figure is the Maximum ROF of THE GUN under perfect conditions IE: equivalent to a labratory benchmark. It has no relationship to the ROF of an operational U-Boat and my Figures have NOTHING to do with it whatsoever. I did quote it but it isnt used in my calculations.
Thirdly, the 'an hour after we had opened fire' doesn't seem as precise in the wording as the 'It was exactly 01:30' bit. Plus, when the hour is up, apparently there are only 20 rounds left. According to the quote, the boat fired 200 shells into her. What happened to the other 80 shells? No mention at all is made of them.
I agree that the first hour in which the 100 Rounds was quoted probably would not be exact down to the last second. When the hour is up there is alot more than 20 Rounds left, Im at work but I think U-109 was carrying 220 Rounds in total. After the first hour there was a break in fireing, the Captain ordered U-109 to close to within 400 Yards and commence fireing again, at this range another large barrage was fired over an extended time which is not given. After that the Captain ordered U-109 into point blank range for the last 20 Rounds.
Also, U-185 was not a Type IXC. She was in fact a Type IXC-40. I have no idea whether the IXC-40 carried the same ready use ammo capacity as the Type IXB, but according to your source (http://www.uboatarchive.net/U-185INT.htm) U-185 only carried 60 105mm rounds - a lot less than the 200 apparently carried on board U-109. Not that this has direct bearing on the matter, but if the ammo loadouts were that different, maybe other aspects of ammunition use were too.
I can find little data on the size of the Ready use ammo store from model to model but it seems clear that the Magazine on various boats was allocated varying sizes of ammunition up to 220 rounds in some cases like U-109 other were alot less.
Finally, it is clear that both 105mm and 37mm shells were fired. But no mention is made of when the 37mm shells were fired. Could it have been combined fire that made up the 100 rounds? It does not state clearly what sort of ammo made up the 100 rounds.
In the book which I did not quote in full it is clear that U-109 opened up with EVERYTHING it had at 01:30 as it was suspected by the Captain that this was a Q-SHIP. The guns included the 10.5cm and the 3.7cm as well as the mountable MG34 and whatever other AAA was onboard.
This caused so much firepower consentrated on the HALCYON that its Radio operator distress call indicated that they were under attack by a German Cruiserrather than a U-Boat.
In short, there is too much left out of the report. We can't calculate anything from this.
In my opinion, the rate of fire reported would be physically impossible for a single 105mm gun. I just do not see how any crew could possibly get a 53lb shell out of a sunken container, across 12ft of deck to the loader, then load it into the breech, wait for the boat to pitch and roll up or down to the desired aim position, and fire, all in 4 seconds. I realise that gun crews are efficient but, as far as I can see, it would take nearly 4 seconds just to lift the 53lb shell out of the box. I can buy the 53 seconds for the rounds hoisted from below, but there's something very fishy about the rate of fire for the rest of the ammo.
Again I dont understand your Focus on 4 Seconds which is deduced from the MAX ROF stated for the Gun. It has nothing to do with my Figure of 53 Seconds per round. In fact the Gun crew has a whole 53 seconds to aim, shoot and remove the shell from the breech before another round will be there ready to load from the magazine. Even if it takes 30 Seconds to fire each ready ammo locker shell off it would take 16 Minutes to fire all 32 Shells, in that time 18 shells from the magazine would have arrived on deck to fire. There is no use of the Magic 4 seconds here.
EDIT: The TYPE IX Seems to actually have a 36 Round Ready container (See edit on the Bottom of this post).
If each round takes 30 Seconds each to Aim-Fire-Unload IE: A ROF of 2 RPM the Ready container will be Empty in 18 Minutes.
If the Magazine ammo is on deck every 53 Seconds there would be another Virtual 20 ready ammo to fire by the time the 36 ready ammo is spent, this would be fired in 10 Minutes at 2 RPM.
In 10 Minutes another 11 shells arrive so that 2 RPM may continue.
This ends up with 77 Rounds fired 1 every 30 Seconds for a total of 38.5 Minutes the remaining shells take 53 Seconds each for a total of 100 Rounds in One Hour.
It's well-researched info, but somehow I doubt the sources, or there is some essential info missing. Plus, I'm certain that some of the source material relates to firing the gun in perfect conditions - conditions that do not relate in any way to combat. If the report is accurate about the '1 hour' thing, I would hazard a guess that the '100 rounds' fired into her over the course of an hour included a good few 37mm shells.
To be conclusive several gun action reports would have to be gone through and averaged as conditions would vary considerably.
Hirshfeld in the text states he was counting every shell from the 10.5cm as he was the chief funker on the boat and his shack is right below the gun and nerby the magazine. Every single shot from the Deck Gun nearly blew him off his seat in the Radio room.
EDIT: From here http://www.uboatarchive.net/U-172INT.htm
DETAILS OF VARIOUS GUNS, AMMUNITION, AND STOWAGE
105 mm. – On U-172’s last patrol, 90 rounds of 105-mm. ammunition were carried, of which 36 rounds were stored in containers on upper deck. Only one kind of ammunition for this gun was carried. It was called Zonenmunition, consisting of H.E./A.A. shells. The projectiles had red marking. The fuze was not set in advance, but would have been set as the projectiles were about to be used. Ready-use locker was abaft the gun. The cover of the locker was hinged at the sides and opened in the middle. It held four rows of nine shells each in steel containers. U-172 never fired any of this new 105 mm. ammunition.
It would appear the Actual total storage of the TYPE IX Ready ammo container was a total of 36 Rounds no 32 as as stated before. The above seems to be a much more informed description of it.
Fair enough. I was playing Devil's Advocate somewhat, as that 15RPM figure is a bit misleading - it certainly threw me off the track, hehe.
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