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Post Info TOPIC: rifle calibers


Commander in Chief

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rifle calibers
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Hi all,
there is 8mm ammunition, 9, I think even 7, but why are there so many calibres without a round number so to speak: 7,62, 12,7 etc. for rifles, pistols and MG's.
Where does that come from?

regards Kieffer

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Legend

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7.62mm is .3 inch, 12.7mm is .5 inch

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..... to answer your question we have to go back to the Franco-Prussian War,  when the Chassepot was the standard arm of the French infantry.  It was 11mm in calibre and used a paper cartridge.  The Germans were armed with their Dreyse Needle gun in 13mm; again with a paper cartridge.
After their defeat ,  the French sought two avenues to perpetuate their dream of le ravanche;  aliances & superior weapons developement.
In the field of small arms this  resulted in a completely revolutionary desgin; the Mle 1886 Lebel.    This system represented the first small calibre, high velocity, multi round capacity rifle in the world.    The genius in the developement was built around the 8mm brass cartridge.  Accuracy and range were achieved by the world's first dove-tailed bullet.   A robust and highly reliable rifle,  it was flawed only by it's tubular magazine and rimmed cartridge.  After it's introduction every country scrambled to come up with something similar.

The Germans responded with their M1886 Mauser; in 8mm rimless round nosed.   An accurate system that served well into the Great War.  But the French still held the edge because their Lebel fired smokeless ammunition;  the M1886 did not.  It in turn was replaced by the G98 Mauser designed around their excellent dove-tailed 8mm smokeless cartridge.  
In short,   all beligerents entered the war with .30 calibre rifles, all of which proved battle worthy.
Many obsolete , large calibre rifles were sold to, or used by other nations( Serbia & Montenegro come to mind .)

 



-- Edited by 28juni14 on Wednesday 12th of May 2010 04:39:24 AM

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Legend

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Indeed, 28juni14 is right about the Lebel. It might be instructive to list those military metallic rifle/machine gun cartridges listed in my aged Cartridges of the World. "R" in the European-nomenclature cartridges means rimmed. BP means the initial issue of the cartridge is clearly described as blackpowder. Calibres are nominal - 11.15mm (.43 inch) is often called 11mm and the calibre (but not the rifles) are apparently interchangeable. On the other hand, those called "8mm" can be anything between 8mm (.318 inch) and 8.28mm (.326 inch) bullet diameter and generally (but not always) the barrel bore across the grooves (between the lands) is varied accordingly.

The smaller calibres (8mm and below) were designed for repeating, self-loading and automatic weapons. The largest (.577, .58, 15mm) were for breech-loading conversions of rifled muzzle-loaders. The 9.5x60R Mauser was the apex of blackpowder design - all smaller had an eye to smokeless powder, even if initially adopted in blackpowder.

It is expensive to change barrel-cutting machines and barrel 'blanks' (the unbored barrels) - that is why particular calibres persist. Germany and the USA both had disproportionate influence, the latter being part of the reason so many sizes look odd-ball in metric.

With metallic cartridges and smokeless powders in all their variety, primers, bullet weights/shapes, chambering/seating tolerances and crimping (as a secondary consideration) it is possible to 'tune' a cartridge a certain amount towards desirable performance characteristics. There is at least one 'sweet-spot' for any combination, for a particular cartridge (capacity, 'conformation'/shape and bore) and a given barrel length which is relatively forgiving of the inevitable small variances in powder weight, burning rate and bullet weight (or chamber/barrel wear). An infinite variety of calibres is simply not required.

Other than that, there are the compromises over conflicting considerations of the weight of ammunition, magazine capacity and (to an extent) magazine reliability (rimmed and short fat bottleneck rounds are a bastard to feed through), effective range (and how that is defined) and 'user-friendliness' (firearm recoil velocity, mid-range trajectory and propensity to jam or be short-charged). The latter is a part-function of (greater) cartridge length, strange to say (some) troops using bolt-action, or even lever-action and pump-action weapons, in the heat of the moment, are quite capable of endlessly re-cycling a fired cartridge without quite ejecting it. Maybe you would have to be there to appreciate the reality.

Anyway, here's the list - mostly WW1 and earlier, all adopted (none 'experimental'). Except the 6.5x57 which while not adopted was a bit more than experimental. And the US .58s because Brennan was interested. For the stated user there were many others for some of these - even so it is doubtless incomplete. Some countries had several rounds in use at the same time - but probably only one 'main calibre'.

6mm Lee Navy (USA) 1895
6.5x54 Mannlicher-Schoener (Greece) 1900
6.5x54R Mannlicher (Netherlands & Romania) 1892
6.5x50 semi-rimmed Arisaka (Japan) 1897
6.5x55 (Sweden) 1894
6.5x57, 6.5x57R Mauser (not adopted) 1893
6.5x58 Verguero (Portugal) 1904
6.5x52 Mannlicher-Carcano (Italy) 1891
7x57 Mauser (Spain, then many others) 1892
7.5x55 Schmidt-Rubin (Switzerland) 1889
.30-06 Springfield (USA) 1903-1906
.30-40 Krag (USA) 1892 (BP)
7.62x54R (Russia) 1891
7.65x53 Mauser (Turkey etc.) 1889
.303 (Britain) 1888 (BP)
8x50R Lebel (France) 1886
8x50R Mannlicher (Austria) 1888 (BP)
8x53R Murata (Japan) 1889 (BP)
8x57 (7.9x57, 7.92x57) (Germany) 1888 ("J") 1905 ("JS")
7.92x57R MG (Netherlands) 1908
8x58R Krag (Denmark) 1889
8x60R Guedes (Porttugal) 1885
.351 Win SL (USA) 1907
9.5x60R Mauser (Turkey) 1887 (BP)
10.15x61R Jarmann (Norway & Sweden) 1887 (BP)
10.15x63R Mauser (Serbia) 1878 (BP)
10.4x38R Vetterli (Switzerland) 1869 (BP)
10.4x47R Vetterli (Italy) 1870 (BP)
10.7x58R Berdan (Russia) 1868 (BP)
11x50R Albini (Belgium) 1867 (BP)
11x53R Comblain (Belgium) 1871 (BP)
11x59R Gras (France) 1874 (BP)
11x60R Murata (Japan) 1881 (paper) 1884 (brass) (BP)
11.15x58R Remington (Spain) 1871 (BP)
11.15x58R Werndl (Austria) 1877 (BP)
11.15x60R (11x60R) Mauser (Germany) 1871 (BP)

11x52R Beaumont (Netherlands) 1878 (BP)- will fire in the
11.3x50R Beamont (Netherlnds) 1871 (BP)

.45-70 US Govt (USA) 1873 (BP)
.577/.450 Martini-Henry (Britain) 1871 (BP)
11.4x50R Werndl (Austria) 1873 (BP)
11.4x50R Comblain (Brazil) 1874 (BP)
11.43x50R Remington (Egypt) 1870 (BP)
11.43x55R Peabody-Martini (Turkey) 1874 (BP)
11.5x50R Reformdo (Spain) 1874 (BP)
11.7x51R Remington (Denmark) 1867 (BP)
12.11x44R Remington (Norway & Sweden) 1867 (BP)
.50-70 Musket (USA) 1866 (BP)
.577 Snider (Britain) 1867 (BP)
.58 Musket (USA - not adopted) 1869 (BP)
.58 Berdan Carbine (USA - not adopted) 1869 (BP)
.60 (15mm) Krnka (Russia) 1867

--Later

7.35 Carcano (Italy) 1935
7.5x58 MG (France) 1924
7.5x54 MAS (France) 1929
.30 M1 (USA) 1941
7.62x39 (Soviet) 1943
7.62x51 NATO 1954 (US) - 1952 as .308 Win
7.7x58 Arisaka (Japan) 1939
7.92x33 Kurz (Germany) 1941
7.92x61 MG (Norway) 1929
8x59 MG (Italy) 1935
8x63 MG (Sweden) 1932
8x56R (8x52R) Mannlicher (Hungary) 1931

-- Edited by Rectalgia on Thursday 13th of May 2010 06:03:18 AM

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Commander in Chief

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Rectalgia wrote:

7.62mm is .3 inch, 12.7mm is .5 inch



sorry, you may call me the dumbo of the week now.


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Legend

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kieffer wrote:

...sorry, you may call me the dumbo of the week now.


What? How is that dumb? The only reason I know anything about rifles is because I was such a lousy shot. Fortunately the targets were paper and my instructor had a .30 cal pencil or I would still be in basic training today. Australia's oldest recruit. "But I wasn't recruited Sergeant, I was conscripted!"
"Shut up Recruit - and give me forty."
Anyway, nothing to be proud about. I was so embarrassed I took up shooting as a hobby to get better at it (benchrest, the most technical of disciplines). I eventually became a reasonable shot. But I digress ...

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Legend

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Not entirely off-topic for WW1 weapons.

Some would put the start of the arms race a little earlier than the Lebel innovation, at the several battles in the Siege of Plevna (Pleven), 1877. The vastly outnumbered Turks held up the Russian-Romanian advance into Bulgaria for several months, earning much admiration from the rest of Europe, partly because, in addition to the single-shot rifles used by both sides, the Turks had 30,000 Winchester repeating rifles firing a .44 rimfire round. These were useless at distance but at 100 yards and under provided devastating firepower. And reportedly, each Turkish rifleman had 600 rounds to fire.

Before closing to such close quarters, the attacking Russians had to endure the long-ranging accuracy of the US-made Turkish Peabody-Martinis (chambered for their 11.43mm - .45 inch - Turkish cartridge). That accuracy achieved mythical status when the siege was recounted by the sympathetic western powers - 3,000 yards was mentioned (utterly fantastic of course) - and together with the quick-fire capability of the Winchesters established an enviable reputation for US arms in Europe, which explains much of that country's extraordinary influence in the small-arms purchases of many countries ever after.

And the Russians/Soviets never forgot. In both world wars they used quantities of M1895 Winchester lever-action rifles with box magazines, chambered for the Russian 7.62mm rimmed round.

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Commander in Chief

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Hi 28June,

thank you for your analysis!
As for the Chassepot versus Dreyse, I think the French were already at the advantage. The Dreyse had problems with the needle that had a tendency to break and I think the range of the Chassepot was longer too.
The Franco-Prussian War was a clash of tactical concepts as a clash of the "spirits" too.
It was the 'elan' and 'attaquer a l'outrance' by the French army versus a less heat headed German approach. With it the 'advantage' of having modern technology without the experience and the right use of it. The French multi barrelled machine guns were an example, using them as light artillery instead as an infantry weapon.
And as every innovation there's is that sleeping danger of staying to long with it.
The 8mm rimmed cartridge was ahead, but as al rimmed ammo a problem in repeating fire arms: unsuitable for clips, tendency to jam or even damage. The tubular magazine was not ideal too. The carbine version of the Mle 1886 had a 3round clip (but as far as I know that was introduced in 1935). As did the Mle 1892 which was the carbine version of the Berthier Mousqueton d'Infanterie. The French left the 8mm theme in 1936, with the MAS.
Which is a bit of an odd weapon, having the bolt lugs at the rear, so you have to pull the bolt quite a way to chamber a round. Apart from that the closing of the chamber was not that perfect. But they were wide spread, in use long after WW2 especially in former French colonies. I only know a bit of these, as the French and Belgian army is one of my favourite 'study' objects. War souvenirs...my uncle let me play with the things, very bad for the innocent child soul and very not-PC today...

regards, Kieffer

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Commander in Chief

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Hi Steve,

that's an impressive overview, a lot of work too, thanks!
The examples I gave, were exactly those where I should had use the conversion table from mm to inches...there you got me!
Still, there are many calibres that look odd at first sight, 11mm and so on. May be I am thinking to metric, used to standard (mainly metric) tools and bits. Every deviation on tools, or specially made drills are costly and there must be a good reason why they're needed for.
So why is 'someone' drilling an 11mm bore in an axle instead of a 10mm...(though I know that cannon drills are specialized tools you don't buy at the local DIY).
And where rose the idea of making the 1888 J and 'the same' 1905 JS cartridge, which are not compatible?
Apart from that I am always fascinated by the technical architecture of different nations.
And for rifles, it seems it's all about two or may three different worlds, the Lee Metford inch calibered and the Mauser principles. With all the conversions and licence built products, mutual influence or not, an interesting thing.

regards, Kieffer

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Hi Kieffer,

Generally when metallurgy improves and powders improve there is an increase in chamber pressures to take advantage, meaning it is desirable that the newer cartridge will not chamber in older weapons if they cannot safely handle it - but I don't know that was such a big factor except with some of the older blackpowder cartridges in that period at the end of the nineteenth century.

There is a change in concept maybe - like the 8x57J (true 8mm bullet diameter) with 226 grain round-nose bullet gives way to the 8x57JS (8.2mm bullet diameter) with 154 grain pointed spitzer bullet at higher muzzle velocity and with less rifling pitch. The new round has a flatter trajectory over 'practical' ranges but less retained energy at longer ranges. In that case the new round is not quite safe to use in the old rifle and the old round is not so accurate in the new bore, but there is not much in the difference - it is only the equivalent of the typical depth of the rifling. Why they did not stick with the same bore I do not know.

The British didn't change with the .303 (which has a .311 diameter bullet) - they went from a 215 grain round-nose to a 174 grain pointed type without changing anything else - but that was not so great a difference.

But why 11mm instead of 10mm? Well, the .44 and .45 were established calibres in America is one reason I suppose. There is more difference than it seems between the two - the .44 is actually .43 (11mm) although I suppose some true .44s (11.15mm) were around. With soft lead bullets it really didn't make much difference. But the .45 really was/is .45 (11.43mm). Except for rimfires, where there were no .45s. But then the .44s were .45. Of course we do have 10mm these days (several cartridges). They are actually 10.15mm (.40). Not to be confused with the .41 (10.4mm).

Oh well, at least the .38s are really .355-.357 which is 9mm and the .32s are more or less 8mm (.312). But why am I trying to explain? - it is all set out most clearly here - http://www.glbarnes.com/projectiles.html

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Commander in Chief

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Hi Steve,

thank you again, this is very learnfull!
I never paid that much attention to ammunition, as I was more interested in the mechanical section of the rifle itself like the bolt mechanism etc.
And math, that was and still isn't my strongest point, all these numbers can be quite confusing. Not to mention the pressure, powder characteristics and so on, which is almost a science on it's own, so thanks again for lightening things up!

regards Kieffer

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Legend

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But wait, there's more! If Brennan was looking in on this he would be muttering about the nominal bore sizes. The attached will have errors but, as far as I can make out it gives the actual Bore Size (in inches) while the Groove Size next to it is pretty much the bullet diameter. It doesn't eliminate the confusion - but it documents it. A few post-WW1 cases have crept in but these help show the picture. Some other data is included too, notably the twist rate of the rifling (shows how many inches to one turn). The fewer means the twist is faster, needed to stabilise long projectiles (like the 6.5mm calibres).

I can find no documentation to support my earlier contention that the twist rate was reduced when the 8x57 went to the lighter, shorter (and slightly fatter) projectile. Maybe they didn't do that - but I don't entirely trust those German figures. Military accuracy is not the most demanding of standards so I think there really was a certain amount of tolerance in the figures.

The table is adapted from Cartridges of the World 1972, Frank C Barnes, edited John T Amber.

[edit] revised attachment.

-- Edited by Rectalgia on Saturday 15th of May 2010 09:07:12 AM

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Commander in Chief

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Hi Steve,

I tried to lure Brennan with that NZ mortar picture, and wrote him a private message too.
He's okay but busy. Hopefully the good man shows up on the forum soon again!
To ammo: I read somewhere that during ww2, when Germany began to run out of almost every raw material, they changed from full core bullets (brass?) to lead filled ones.
Is that correct? And did that happen in the Great War too?
About the .44, you probably know this poem, or epitaph.
Here Lies Lester More
Killed by 6 bullets of a .44
No Les No More

don't give up upon me,
Kieffer

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kieffer wrote:

...
To ammo: I read somewhere that during ww2, when Germany began to run out of almost every raw material, they changed from full core bullets (brass?) to lead filled ones.
Is that correct? And did that happen in the Great War too?


I have no information on that right now, not aware of any military use of solid bullets except lead (which is generally no good for higher velocity, needs jacketing for that except for the few 'squeeze-bores' that crop up from time to time and I don't know how those handle bore fouling), not in many, many years - perhaps some of the larger calibres like in the 1"/25mm? There was a convention (pre WW1) I think against using explosive projectiles less than 1 pound so those larger-than-rifle calibres might be used with all sorts of projectiles for close-range (relatively) high velocity and penetration.

In rifles, solid brass projectiles (perhaps with some jacketing to reduce fouling) were used in the big-game types for increased penetration without the deformation of the projectile. This would be for elephant, rhinoceros, maybe Cape buffalo. With concerns about lead pollution solid and composite non-lead rifle projectiles have emerged again recently but mostly they don't match the economy or ballistic performance of lead as a major component (exception being tungsten composite which can be ballistically matched to lead or exceed it).

Lead has a high density, incorporation as a core permits projectiles of high 'sectional density'/high 'ballistic coefficient' meaning retained velocity and energy at a distance while the jacket holds it together for penetration and reduces bore fouling. But it increases chamber (and barrel) pressure compared to any equivalent-sized projectile (except gold, platinum, uranium, thorium, thallium, palladium, ruthenium, rhodium, rhenium, hafnium, tantalum, iridium, osmium, tungsten, mercury and maybe one or two I missed - most of the artificial elements of course). In practice smallarms pretty much evolved to use the lead or mostly-lead projectiles (even air-rifles).

Footnote on small calibre squeeze-bores. I seem to recall that the late Arthur Langsford, then owner of Myras Sports Store in Broken Hill, Australia offered a rimfire squeeze-bore back in the 1980s or 90s, based on the .22LR. It never caught on, I guess the .17 high-velocity rimfires which have been developed since provided the same or similar velocities without traumatising the projectile (and barrel). His idea would have a substantial benefit in ammunition costs though so I suppose there were some difficulties/frustrations with that conical bore implementation. Sadly he wasn't around long enough to solve any such problems. Further, Arthur himself designed a .17 rimfire based on reformed .22 Magnum cases about 30 years before the current crop of commericial .17 rimfires - though I think the squeeze-bore was a later development because of the cost of the reformed ammunition his version of the .17/22Mag needed - and suppliers were reluctant to provide the primed cases I seem to recall also.
kieffer wrote:


About the .44, you probably know this poem, or epitaph.
Here Lies Lester More
Killed by 6 bullets of a .44
No Les No More

don't give up upon me,


Heh heh - if I knew that ditty I had forgotten it, thanks. No, I don't think anyone would be giving up on you Kieffer, they would miss out on such interesting stuff if they did!

[edit] - correction to the name of the Australian squeeze-bore developer (memory like a sieve, I need an upgrade).

-- Edited by Rectalgia on Saturday 15th of May 2010 08:30:21 AM

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Commander in Chief

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Hi Steve,

thanks again! I will study your analysis thoroughly first before asking further!
I'll later post a picture (1914 dated) from the notorious dum-dum's. With the rumours about the franc-tireurs in Belgian villages it seemed to be quite a news item in 1914.
The convention, I must look that up, it's the Conventie van Den Haag or Haguer Convention or the Genieva Convention, I put my money on the first.
Dum dum was and is certainly forbidden. As are more hack saw inventions as for instance bayonets with a jagged edge, if I am correct.

regards, Kieffer

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Hi Kieffer,

I will extend that table when I have time, to add the columns of bullet weight, muzzle velocity and 200 yard mid-range trajectory (at the time of WW1 if the bullet type changed before then) which will allow comparisons of performance. And I will add the poor old Canadian Ross - it was a front-line weapon in significant numbers for half the war.

Dum-dums - yes interesting though regulation is pointless really. The Spanish with their old 11.5mm Reformado cartridge caused the US troops in Cuba more concern than the new repeating rifle 7x57 the Spaniards also used because those old brass-sheathed bullets would shed their jackets on impact and cause terrible wounds which always got infected. But the Reformado was within convention. The British 303 had a light nose and tumbled when it hit, causing great damage. Also within convention (the nose was for ballistic effect). The Italian 6.5mm Carcano (and other 6.5mm) had a very long projectile, barely stable in flight, which tumbles when it hits. Again, within convention. I have used that (carbine) and can testify it does great mischief (no, no I never shot people with it, only defenceless furry things).

Yes, the British were quick to accuse the Germans of using saw-blade bayonets but British engineer and artillery troops used those things until just before and in earlier times infantry too. The British found in their campaigning that troops broke swords cutting firewood with them so it was a good idea that sword bayonets should have a saw-back to do that job. And now again, many of the knife bayonets have the saw-back (and most of the survival knives). It is no doubt still against convention to have the main cutting edge serrated but what is the difference? The Khmer Rouge used the sharp, serrated parts of palm fronds when they wanted to get messy and personal.

Steve

Hmmm ... talking of the Reformado, I see I have that entry wrong in several particulars, in one of my earlier posts (and can't edit it now). It should read:

11.5x57R Reformado (Spain) 1867 BP

-- Edited by Rectalgia on Saturday 15th of May 2010 06:33:01 PM

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Commander in Chief

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Hi Steve,
I agree, these conventional regulations are a paradox, as is the concept of 'clean weapons' and others. Being bayonetted, having the of kilograms of steel plus that of the man who is giving you the treat, saw blade or not...
I think they try to ban land mines nowadays...
Not to digress or to avoid your analysis, I am still reading them (I am risking a burn out!) but to the convention of The Hague: I think there were actually two, one from 1899 and one from 1907, to make matters complicated preparations were done in Brussels 1874.
These regulations were complicated and elaborate, from rights and duties for belligerent and neutrals to detailed prescriptions on weaponry. For instance sea mines, which were/are 'legal' if anchored or when being the floating type, but the latter only for a short period: after 1 hour they have to be defused or neutralised. Anchored mines must be of such a construction that they can not defuse when on the drift. And this is only one rule!
The picture shows forbidden dum dum ammo. From a magazine early 1914, the article has that upset tone like "how on earth can a nation think of using these perfide bullets".

regards, Kieffer

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kieffer wrote:

...
The picture shows forbidden dum dum ammo. From a magazine early 1914, the article has that upset tone like "how on earth can a nation think of using these perfide bullets".


Hi Kieffer,

As every 'civilised' hunter knows, it is all about the selection of projectiles yet even here there is some guidance from the world of (other) animals as Robert Ardrey (The Territorial imperative etc. would have it). African hunting dogs (the wild dogs) which swarm their prey do not need to kill their prey outright, often they eat it alive (shudder) - tastier that way. The big cats which are solitary or hunt in small groups kill theirs straight away. They can't afford injury to themselves or the waste of energy if it escapes. The military is expected to kill cleanly (bombs, shells and grenades don't know that) yet their adversaries can fight back, even mortally wounded, or escape and come back later.

Whatever the high-minded like think, it is a dilemma for the traumatised troops in the front line. And there is no black and white. I mentioned the .303 and its ballistic design which coincidentally makes it a little more deadly. And the Reformado, the brass sheathing which reduces bore fouling becomes splinters and shards and a source of/aid to infection. Even those earliest cartridges were of complex design for ballistic purposes which is the way to make 'practical accuracy' better. Who gets to compromise the safety of one's own troops for the benefit of the enemy? But there are consequences if 'world opinion' sees the weapons as barbaric or really really dangerous (who gets to feel them next?). It is ludicrous but it is human. Or even more basic than that.

Attached is detail of the first British smallarm metallic cartridge. What's the difference between that and the dum-dum? Only the intent, I think. Take out the expanding base plug and the wooden nose plug (or later sealed cavity) and the trajectory, already like a 'rainbow', becomes worse. The 200 yard mid-range trajectory (sorry, that one figure imperial measurement) is already a third of a metre, meaning that is how high the bullet shoots at 100 yards when aimed at 200 yards. With that trajectory, not shown but a consequence of that same curve, it will be a whole metre below the sighting line at just 250 yards! Take out the 'ballistic improvements' in the projectile design and it will be far, far worse (but I would be guessing to say how much). That is the extreme example but similar in principle to later developments.


It is a fine line to walk and requiring the judgement of a Solomon.

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Hi Steve, thanks again, you must have had a lot of work! Let's pray that your writing won't be ripped by that patriot fellow!
I read somewhere that, though officially banned, soldiers made their own dumdum by cutting in grooves in the bullet, this giving the effect of 'flying pieces of barbed wire'.
But like the serrated bayonets, I don't think front line troops did do that very often. I don't know if the stopping power (another 'euphemistic' expression) was that significant to make much difference. For inflicting wounds only, well many who "had seen the elephant" had a certain attitude to soldierly behaviour. Showing off your special bayonet as a novice to your comrades, I think reality made a quick end to that.
And may be there's a psychological aspect to it: you're aiming a rifle direct on the man, throwing a grenade is less 'personal' I presume. I still remember that uneasy feeling when, as a recruit, you had to aim and fire during manouvres, on 'the enemy'. And that was only firing blanks.. (I always wondered, when in 'old' Berlin, house facades if the plaster was old, were pocked with dozens of bullet holes, whilst a window offers quite a big target. I think that in war situations almost every man is vollying around, adrenilised and feared).
I agree: it's a Solomons judgement, choosing between bad and worse, and all a gruesome business. With a highly interesting aspect, historical, technical and even esthetic.
Hard to explain all that to people who are not that interested in military thematics.

regards, Kieffer

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You may find this of interest if rather grusome...

"Ricochets. - Injuries inflicted by ricochetting bullets are very frequent. They are observed in the proportion of 1 in 3 of all cases."

"A projectile ricochetting from the ground is deflected, and strikes the body obliquely or transversely. It is put out of shape, flattened, turned out of its course, broken up, separated from its envelope, and so the number of injuries to which it gives rise is multiplied. To be put out of shape a leaden projectile must have a velocity of 450 metres, a bullet with an envelope a remaining velocity of 750 metres.

The S bullet, formed of hardened lead and covered by its envelope, is more easily put out of shape, flattened, and broken up on striking the ground, than the D bullet, which is made of brass.

Injuries inflicted by ricochetting projectiles are more serious than those caused by bullets fired point-blank."

On Dum Dums...

"
At the outbreak of every war there are always questions raised with regard to the employment of dum-dum bullets. It is so to-day. We have seen wounded men in the present campaign concerning whom this old error has been brought forward. The terrible injuries that have given rise to this mistake differ so greatly in character from those usually observed that it seems impossible to attribute them to the action of a bullet which causes but very small apertures of entry and of exit.
This, however, is not so. In such cases it is a question of explosive shots due to projectiles of very high velocity becoming more or less broken up in their course through the tissues. The fury with which our soldiers have many times fallen on the enemy, and the fact of their being hit by bullets from very short distances, sufficiently account for these wounds that need no further explanation."

From:  Extracts from War Surgery (1915)
by Dr. Edmond Delorme -- (Translated into English by Dr. H. Méric)


http://www.gwpda.org/medical/delorme.htm 

The link has some usefull info on WW1 bullets and their effects...

Cheers



-- Edited by Ironsides on Monday 17th of May 2010 11:37:46 PM

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Excellent reference Ivor, thanks. It tells it precisely how it is, I think.

Yes, it is extremely gruesome. My only problem is that people forget just how gruesome it really is (I really object to all those 'war movies' where the deaths are so neat and clean and poetic and 'cinematic' and unobjectionable - war is horror and pretending otherwise is an even greater horror in the end). But I'm preaching to the choir here.

I guess the nearest thing to the sanctioned dum-dum these days would the the duplex round for machine-guns (ball, duplex in English/NATO terminology). The rear projectile is designed to increase the spread of fire and I would be very surprised if it was not tumbling, virtually from the offset, and that will cause extreme damage to unprotected targets at short to medium range. I think most forces have it their armouries, just Google it.

But don't click on the china-defense-mashup.com link about the Chinese 12.7mm - despite Norton Safe Web assurances that link is hacked with an exploit at the moment1 - 'someone' has covered their tracks very well and wants to punish intending viewers. Ah, one doesn't have to be paranoid to survive the internet, but it helps.

Steve

1HTTP Fake Scan Webpage 5, Severity: High

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High guys, slowly getting the head up over the sand bags.

Yes I was muttering about "nominal" calibres!

Couple of notes re Black Powder small calibre rounds (transitional almost always) - these are often molded compressed BP with a central hole to give balanced burn rates - the pressures attained in FULL length late C19th or Early C20th rifles are very close to smokless powders. Next if the "correct" formulation of powder, binding resin, barrel length, charge etc is used they do produce very small amounts of "smoke". The trap is volume or sustained fire creates a localised high pressure zone so it does not clear away. At night the problem is phosphoressence - the stuff hangs & glows. It can be quite pretty if it wasn't potentially deadly - ie getting you seen!

The above is why the LeeEnfield becomes the SMLE once issues with its length get recognised & why the Germans adopt the Kar98 over the Gwr98 during WWI. The Kar98 is NOT a carbine it was in historical parlance a "musketoon" or older still a Dragoon model for the Engineers, Artillery & Dragoons. Cavalry had a real carbine (much shorter again) unless of course one cheats like dastardly Brits (all with SMLE), Russians (Dragoons & Cossacks with real rifles others with long carbines), Turks & some Balkan blighters (with combinations of KAR98 look alikes & real rifles! Of course all these unsporting chaps expected cavalry to dismount (shudder).

The next issue is smokeless powders, Note these often aren't early on - paticularly at night where they glow spectacularly. Further the big give away for smokeless powder fire is dust, charing & combustion of small particals!  I won't describe the variations in developement of smokeless powders other than mentioning it had much to do with 3 starting points - gun cotton, nitrocelluose, nitroglycerine. Then what else & how else was done to & with it. I stopped following it when the time line reached the 1950's with close (only close mind you) convergence - since the 1970's its started to diverge again.

The above affects & is affected by the form of the propellant - grains, prisms, tubes, rods, dilled or not etc. Tubes & drilled propelents tend to give constant burn rates (as something burns from the outside the surface reduces so burning slows, if it has a hollow centre - this burns gining an increased surface area so "balances"), Undrilled etc give high initial & declining later pressures, multiple drilled (cored) geometric can give accellerating burns. These all affect bullet acceleration & velocity etc as it goes down the barrel (giving increasing volume so declining pressure). Equally important is the nature & quantity of ejected propellant - as unconsumed, being consumed, residue etc etc.

Then we get to bullets, barrels etc. These all have very significant effects especially as to what material is used & how things are manufactured. Now on this I am / was only a tryo - learn't just enough to really hurt my head but here is an example that is mostly right in principle.

The British 0.303" SMLE. The barrell was changed from a full length forged blank that was bored & rifled as 2 process (when it was initially BP). The barrel became a short oversized blanked of nickel steel (? memory is fuzzy - the steel that hardens on working) that was punch bored, which stretched it to length plus riflerd it in 1 process & then "light finished" (PLSE don't ask me to describe this - it gets dropped for WWII) & later is chromed. The why is heavily related to British Cordite - a nitroglycerine propellent, in tubes so constant burn rates, HIGH temperature, (if the powder is good) very low residue & ejectant but at HIGH temperature & gives a flame caused as much by comsuming airbore particulate & the cooling agent (vaseline petroleum jelly - less is used once barrels are chromed) as anything else.  This combination required the barrel changes to reduce wear (barrels harder, propellant cooled & then barrels coated/chromed), fouling caused mostly by wear & loss of accuracy - both get reduced. It was path that the Brits could take as British bullet lead is high in antimony (& some other things too)- giving high heat tolerance, hard etc but once "damaged" expands horifically. The intiall 0.303 round caused much fuss as to get it balanced with its very long point, the bullet was formed with a heavy jacket & had a small steel cone "dropped" in to the tip & then was filled giving a base cavity. If the process was not perfect (remember ammo is made in government establishments or bought from the lowest bidder) the point breaks - and one gets.........
The round gets redesigned as much to simplify as to molify actually, this rebalances it & makes it lighter, cheaper & simpler for others to make (& fewer expense resources eg copper nickel alloy etc, no small steel cone to be machined etc) & allowing/causing it to be boattailed (though this may have been largely incidental to the other work).

Got to go but will try & get the latest conversion (now weeks if not months old) written up at the weekend plus (being greedy here) add some more on calibres re WWI (& the end of the C19th start of the C20th).

Glad to see your all going well.

Regards,

Brennan

-- Edited by Brennan on Tuesday 18th of May 2010 11:47:51 AM

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Hi Brennan,

Thanks for that!

On the .303 Mk VII round, I have heard of Bakelite and aluminium being used as a nose material (underneath the jacket) too - not sure how authoritative the Bakelite story might be might be offhand, I would think it impossible frankly, but Skennerton's book confirms the initial Mk VII was 160 gn with the aluminium tip and was very short-lived. The boat-tailed VIIz was introduced in 1938 (after many years of experimentation) and was supposedly a (single) grain heavier than its predecessor at 175 gn - not sure whether nor not to take that with a pinch of salt - even the highest-quality match projectiles will have a few tenths of a grain variance within the same batch (more between batches), the best US specs for both their 7.62x51 NATO and 30-06 allowed for 3 gn variation. Whatever.

Oh, and boat-tailed projectiles tend to increase chamber throat and barrel erosion - a good argument for chroming or high-spec barrel steels (chrome-moly etc).

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Hi Steve, the bakelite or bakeliet in Dutch, as it is a Belgian invention: if they used that, than it's interesting to know how they did that, technically spoken.
It's a resin that is hardened by pressure, a lot of pressure. It's rock hard but breakable.
A promising plastic it was, but with limitations, as it's merely impossible to produce big objects, so bigger than radio's, telephones, hair dryers etc. it never came, though they tried a bit with furniture. So how they managed to get a jacket on it, or get it inside a jacket, I don't know.
Alas, much more I can't attribute on calibres, but I keep on reading your analysises!

Hi Brennan, welcome on the stage!


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a small addition: German artillery fuses in ww2 had small bakelite containers and I think they had some other bakelite drum or box like items too
Kieffer

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Adding my bit to the diversion, the British WWII Offensive Grenade (No.68?) was called by the troops the Bakelite Grenade as that was what its casing was made of! The New Zealanders practice was to always wear the greatcoat (if they could) when using it as they could stay on their feet & keep closing. The comment from the troops was that, the Greatcoat provided enough protection that the No.68 was "comfortably survivable" at as close as 7 yards even if still upright! I take that with a grain of salt as by then the NZ'rs were very experienced troops & were quite prepared to take casualties from things like artillery shorts (being well known for staying 50yrds closer to the barrage than most others - ie 50yds or less behind rather than 100 yrds plus) or accidental MG grazing to keep effective suppresion up in the attack. Safety zone were almost inevitably halved & some times reduced further!

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Bakelite - trouble with it is it chars at high temperature. If used in a projectile I guess it would need to be 'dropped in' to the jacket nose and the main, lead, core extruded in behind it. I don't know the temperatures used in production (which might be the first stumbling block) but it all sounds sort of fiddly - it would be simpler by far just to leave a cavity and close the nose of the jacket over it. The Mks II-IV (1895-1898) dum-dum were like that and hollow-points to this day are made the same way, it is just that the nose wasn't/isn't closed with HPs.

It seems the upside-down projectile manufacture (ie, filling to a closed nose) may have been used for the steel and aluminium tips anyway and I guess the complexity-precision problems are nothing compared to that of maintaining concentricity in the steel-cored AP rounds.

But Bakelite? Well, just a generation or two before they used wood, for a while, in the .577 Boxer (Snider) though that was a far simpler proposition cold fitting into a cast lead, un-jacketted bullet.

Incidentally, the aluminium tip type (behind a thin jacket) would probably have created quite a flash when it hit anything unyielding at short range - when the vaporised metal ignited - aluminium of course burns just like magnesium but just needs a little more heat or oxygen. But apparently there were accuracy problems with it, perhaps the concentricity question again. That is a huge issue for accuracy with any rotating projectile.

And the Bakelite grenade? Yes, that was the 'orrible No 69 (an unforgettable number) and apparently still in the Aussie 'books' in the mid/late-sixties (we were taught about it then in SME - the School of Military Engineering) though that might have been just in case we stumbled over an old 'blind'.

If the tape and pin had detached there was no safe way to defuse it, you essentially had a super-sensitive 'trembler fuse' in your hands. http://visualcollector.com/VisualCollectorLinks/HowItWorks/C-No69MkI-L.jpg. Well, that's okay, there's actually no safe way to defuse any expended munition and sappers are expendable. Incidentally, the tapes were quite long if I recall correctly, contrary to the impression that might be given by the above sectioned photo, and it took quite a few rotations for it to unwrap.

I hadn't heard of the greatcoat trick for training with the 69 but that sounds entirely feasible - those things must have been a real swine to throw with the correct 'spin and twitch' to reliably unwind the tape (which would not exactly be helped by being swaddled inside 20 pounds of wet wool - but confidence is the key). I seem to recall there were WW1 types that used the same/similar system to arm the contact fuse. The whole process requires a degree of composure and concentration which is quite improbable in a battlefield, IMO.

-- Edited by Rectalgia on Wednesday 19th of May 2010 07:16:11 AM

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Hi Steve,

Bakelite: a few years ago I got a lecture about the stuff, but...I am not that sure anymore if my recording is accurate on the pressing part. I better look that up. The old memory starts playing games with me.
Wood: I wanted to start a topic on that material, by posting the French crosbow/grenade launcher, alas no one responded. I'll give it another try.
I think Dutch blanks for their Hembrug Mauser were having wooden bullets.
Bakelite again, it's still produced, under another name. As it already was, avoiding the patent, by Philips (the Dutch electronic company with the smart name because almost everyone in Germany think it's German, overseas they think it's 'theirs'..): they called their bakelite 'philite'. The credits anyway go to the Belgians, who invented more great things as for instance the saxophone, well how's that for a little digression..

regards Kieffer

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kieffer wrote:

...
Bakelite again, it's still produced, under another name. As it already was, avoiding the patent, by Philips (the Dutch electronic company with the smart name because almost everyone in Germany think it's German, overseas they think it's 'theirs'..): they called their bakelite 'philite'. The credits anyway go to the Belgians, who invented more great things as for instance the saxophone, well how's that for a little digression.. ...


No digression at all, you've evidently forgotten about the flame-thrower trumpet - http://img444.imageshack.us/ifs/287/img401/2/flametrumpet.jpg. Alas, that was invented by an American if I recall correctly, but he may have had one or more Belgian parents.

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Hi Steve!
I am stunned. Stupified. Catatonic. You achieved what many people around me tried to without success: I have no reply.
The day has just begun, the sun shines, and all I can see is an antartic landscape.

regards, Kieffer

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Dont know if this is any use its a list of Baekeland patents from google patents maybe theres some answers in there certainly it seems it needs fairly high temperature and pressure to mould Bakelite....

Baekeland patents

Bakelite patent

Cheerssmile

-- Edited by Ironsides on Wednesday 19th of May 2010 10:21:35 AM

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Ironsides wrote:

Dont know if this is any use its a list of Baekeland patents from google patents maybe theres some answers in there certainly it seems it needs fairly high temperature and pressure to mould Bakelite....


Thanks Ivor - Seems like it could be possible to incorporate, maybe even to partially mould the tips, in projectile manufacture. I've seen Bakelite partially destroyed by heat (24V circuit breaker, out of a WW2-era aircraft of some sort I think) but no telling what the temperatures involved were (electric arc) and they could indeed be well in excess of those encountered in bullet making. Most Bakelite formulations seem to be stable enough for continuous duty up to 250°F but that's another matter.

All of which begs the question, "Why?" As said, the obvious thing would be to just leave an air cavity under the 'nose cone'. I suppose the answer might be because that would remain very close to the hollow-point projectile which became a prohibited type under one or several of the St Petersburg Declaration and the Hague Conventions (presumably the second Convention of 1907 in particular since they - hollow-points - were happily employed 1897-1905). Unusual for the Imperium to be overly concerned about world opinion at that time I would have thought - but no doubt there were pragmatic reasons as well.

-- Edited by Rectalgia on Wednesday 19th of May 2010 06:07:44 PM

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kieffer wrote:

I am stunned. Stupified. Catatonic. You achieved what many people around me tried to without success: I have no reply....



Ah, you are evidently stunned by the instant recognition that it is but a short half-step from the flame trumpet to the mellifluous flame saxophone, an adaptation trivially achieved by any artificer in a trice! And indeed such a weapon would strike fear in the heart of any aeronaut - I would expect the commanders and crews of Zeppelins in particular to be awed and apprehensive, and with very good cause.

-- Edited by Rectalgia on Wednesday 19th of May 2010 05:43:20 PM

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On the issue of an air cavity in the nose I can see 2 issues.  1st that the tip would be even more likely to break which would give a round effect exactly like those prohibited by convention. The 2nd is reliably achieving the required cavity in WWI or earlier, with the consequences of this being a regular area of variation - affecting the balance of the bullet.

We are dealing with a time when the target shooting gurus (read nuts) wanted the SMLE withdrawn because its bolt locking lug system deformed in use such that it affected accruacy over 1500 yards!!!!!. The fact that the SMLS's action was the smoothest & fastest of all contempories & had no loss of accruacy up to 1200 yrds - the absolute limits of even the most favourable views of even the BEF's musketry, plus the action allows one to keep sighted while working it - something I have never seen someone do with a mauser action!

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Rectalgia wrote:

 



Ah, you are evidently stunned by the instant recognition that it is but a short half-step from the flame trumpet to the mellifluous flame saxophone,

Hi Steve, here a very rare picture of a poilu carrying a flame throwing sax, a highly unpopular weapon by the "hairy" ones.


Attachments
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Brennan wrote:

On the issue of an air cavity in the nose I can see 2 issues.  1st that the tip would be even more likely to break which would give a round effect exactly like those prohibited by convention. The 2nd is reliably achieving the required cavity in WWI or earlier, with the consequences of this being a regular area of variation - affecting the balance of the bullet.



Yes, I can see that but it is a readily achievable technology as far as consistent cavities go, easier perhaps than a projectile with a 2-part solid core. Some of the benchrest projectiles 'in my day' were essentially manufactured in backyard sheds though admittedly they didn't finish rolling over the jacket nose.
Brennan wrote:

We are dealing with a time when the target shooting gurus (read nuts) wanted the SMLE withdrawn because its bolt locking lug system deformed in use such that it affected accruacy over 1500 yards!!!!!. The fact that the SMLS's action was the smoothest & fastest of all contempories & had no loss of accruacy up to 1200 yrds - the absolute limits of even the most favourable views of even the BEF's musketry, plus the action allows one to keep sighted while working it - something I have never seen someone do with a mauser action!


Hmmm ... well we mustn't forget the "F" class "big bore" required a smaller inner bull to restore competition because everyone was getting perfect scores - and those things invariably have a modified Mauser action. Have to admit, firing military Mausers, one does tend to take them off the shoulder between shots but I think that is training/practice. But that didn't happen when Lee Harvey Oswald was behind the butt. You might quibble that the Carcano is a Mannlicher but really that is just the clip 'magazine' system. The bolt resembles nothing else as much as a garden-gate latch but I think it is technically "Mauser-action" (front locking, anyway). Here it is in action - http://www.youtube.com/watch?v=h4c5Zr7hzzA. Hmmm - that includes a minor, split second, 'hangfire', must have been using mil ammo, that stuff is getting pretty old, but that shooter knows his stuff, most people would have had that bolt handle lifted before detonation occurred.

And when I was using my little Tikka .22/250 I never needed a second shot. Sorry the devil made me do that.

But yeah, even a thousand yards is ridiculous outside of sniping circles. Few people appreciate how easy it is to clear miss through misjudging the range when you have a trajectory with a bullet drop - muzzle to just 600 yards in hundreds (.303, approx) - 0", 3", 13", 31", 58", 97", 148". The sighting line offset takes very little of the sting out of that. Even fewer would credit the extent of wind-drift. 18" at 600 yards with the gentlest of zephyrs (5 miles per hour), 105" with a moderate breeze (30 mph). And all of that ignores the angle of elevation/depression effects - multiply line of sight range by (1-Cosine of angle) - quick, where's my theodelite?

All things considered, I think it is "hopeful" to expect any better than 4 MOA (near enough to 4" spread at 100 yards, 16" at 400 yards) as practical accuracy from a "full bore" with standard wartime ammunition and an issue rifle in ideal (calm and collected) field conditions. But yes, with the SMLE it certainly was possible to put them down very quickly - and, with 10 rounds loaded, it soon showed who hadn't fully cleared out the packing grease under the woodwork! (I think we had that discussion before).

-- Edited by Rectalgia on Thursday 20th of May 2010 07:57:59 AM

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kieffer wrote:

...Hi Steve, here a very rare picture of a poilu carrying a flame throwing sax, a highly unpopular weapon by the "hairy" ones.
Ah, being somewhat 'piled' myself I can well appreciate their sentiment. They should have held out for the utterly awesome flame-thrower tuba. Here is a replica, without the flame attachment due to difficulties in obtaining an end-user certificate http://www.oddmusic.com/gallery/giant_tuba.jpg.


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Ironsides wrote:


Dont know if this is any use its a list of Baekeland patents from google patents maybe theres some answers in there certainly it seems it needs fairly high temperature and pressure to mould Bakelite....

Hi Ironsides, the pressure, may be my memory did'nt let me down...

Bakelite was still extensively used in the former DDR, (in western Europe it ended in the 50's) electronic parts mainly but, for toy train fans, the Zeuke factory had a nice range of bakelite gauge 0 trains, and there were quite a few DDR toy makers with nice trucks, cars etc.

Kieffer



 



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kieffer wrote:

Hi Ironsides, the pressure, may be my memory did'nt let me down...
No, no Kieffer, you memory is good. In one of those links Ironsides provided is US Patent 1,111,285 which contains the information (paraphrasing a little): The preferred temperature range is 280-300°F at 50-100 pounds/square inch (3.4-6.8 atmospheres/bars, near enough for each), AND which is consistent with steam pressure at the temperature BUT faster setting with good results can be obtained with higher temperatures than those given which are merely "convenient" (AND higher consistent pressures implied). At 300°F steam pressure is 4.7 atmospheres, so "near enough for Government work."

At 394°F the indicated steam pressure would be 22 atmospheres, to stick to the tables I have to hand, and I am quite sure the process would have been 'sped up' to such levels and beyond wherever possible (as a matter of "economics").

-- Edited by Rectalgia on Thursday 20th of May 2010 09:28:33 AM


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Not wishing to get a reputaion as a nay sayer!

On economics the problem often is that the energy cost even in modern plant is geometric (ie multiplicative) as temperature & pressure rises. In the 19th Century the relationship was often Exponential!!! This with a number often well over 2 for the exponent!


The situation is made worse by declining efficencies in harnessing energy outputs at higher levels. Please note the most efficent use of petroleum before modern turbines etc. was a diesel engine & that rates at 48%. Hence electric subsitutes like cars are only worth while if the electricty isn't hydrocarbon generated!

Transmission is an entire new black hole - especially pre 1950's. There are damned good reasons why almost all significant industrial plants had their energy production literally on site! Hence the ability to equate coal with energy in some strategic simulations for industrial output!

Short of emergency / war measures or new &/or breakthrough plant I suspect not much use would have been made of faster process at higher temps & pressure! Especialy as increased pressure & temperature would decrease the time between plant failures &/or replacement.



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