Nice Work if you can get it …
|Michael Gilligan||30/09/2021 10:15:18|
20057 forum posts
This paper was referenced on Ars Technica , this morning: **LINK**
Yes, it’s about gunpowder … If you don’t like the subject matter, please don’t bother following the link.
|Nick Clarke 3||30/09/2021 10:32:44|
1391 forum posts
Nearly 50 years ago a friend who was a history teacher (and model engineer) was asked to teach some science due to a shortage in that department.
Until very firmly told to desist he did some excellent experimental chemistry on gunpowder investigating the effect of different mixtures, size of particles and the difference (if any) between bone charcoal and wood charcoal.
The kids loved it and no one was hurt but if H&S had been a thing then heaven knows what would have happened!
|Andrew Tinsley||30/09/2021 10:39:04|
|1610 forum posts|
Fascinating find. Thank you Michael.
|Mick B1||30/09/2021 10:39:26|
|2157 forum posts|
It looks like quite a serious piece of work and would take me quite a bit of time to get my head around it properly. (Afternote: if ever! )
I can remember standing on the gun platform of a Tudor coastal fort and noting the spit of land that the extreme end of one training traverse pointed at. Assuming the gun could cover the navigable width of the channel, that suggested an effective range of a bit over a mile - perhaps using one of the long-barrelled culverin variants of the period. I hadn't known they were that good, that early.
Edited By Mick B1 on 30/09/2021 10:59:28
|Nigel Graham 2||21/12/2021 22:33:42|
|2009 forum posts|
I live near Portland Harbour, or Portland Roads as it was called before being enclosed by the Breakwaters.
Henry VIII had two forts built to protect it, one over on Portland (and intact) the other a ruin on the mainland opposite, in Sandsfoot Gardens.
The information-board for the latter tells us it had culverins - with long barrels for their bores - with a range of just over a mile, so the forts' arcs of fire partially overlapped in the middle of the Roads. Not the full width, which might have been worrying for your comrades in the opposite fort! It does suggest the Tudor armourers were well aware of the effect of a long barrel on range and accuracy - the length presumably maximising the useful expansion of the gases.
Portland Castle's gun floor is only a few feet above sea-level. Sandsfoot's, some 30 or 40 feet above, at a guess, as the castle is on top of a cliff whose retreat by erosion is partly responsible for the building's ruination. I don't know what effect on range that would have had.
A problem with gun-powder is the huge amount of dense, acrid smoke it produces. Not so bad in a sizeable fort with the muzzles run out through the gun-ports, but it must have been grim in more enclosed spaces, even from small-arms. Tillietudlum Castle, near Lanark (Scotland) has two "capuchins" ( If I recall correctly) across the dry moat, to cross-fire along the trench at any attempted frontal attack.
A capuchin is a 17C pill-box, with small musket ports below a low roof. Those at Tillietudlum each have just one entry / exit doorway in one end, the other end blank against the moat wall. The poor soldier at the outer end would have had the full length of the smoke-filled, poorly-ventilated building, perhaps twenty or thirty feet, to brave to reach the exit.
It appears these things were built at quite a number of forts, but became so untenable so rapidly from the defenders' own flintlock musket smoke, that they were discontinued relatively rapidly.
|Speedy Builder5||22/12/2021 06:52:54|
|2590 forum posts|
Nick C. Rev Lancaster of Kimbolton School Bedfordshire developed his own fireworks and became one of the countries leading firework designers.
8469 forum posts
'Caponier' rather than 'Capuchin' I think.
On the subject of dense acrid smoke, I'm just finishing Vol 2 of Kuropatkin's 'The Russian Army and the Japanese War'.
The Russo-Japanese of 1904/1905 is interesting because it was the first modern war: steam transport, barbed wire, concrete, telecommunications, high explosives, QF artillery, machine guns, balloons and much other scientific nastiness.
Both sides used smokeless powder. As a result, General Kuropatkin says it was no longer possible for a commander to manage battles by standing on an eminence with a telescope and watching the smoke. In 1904, fighting men were all but invisible. Wellington and Napoleon would have been baffled by lack of information! Understanding what was going on required good maps, telephones, telegraphs, and wireless connected to a commander hidden deep and safe inside a shell-proof bunker. Messages delivered by horsemen were too slow and vulnerable...
|337 forum posts|
There is a very nice gunpowder proving mortar on dartmoor. Just type in dartmoor proving mortar to see it. They checked the quality of the powder batches with it.
|Mick B1||22/12/2021 12:24:26|
|2157 forum posts|
I think this is the beast, as it was in 2009 anyway - mounted on a 'coehorn' I believe. The powder mill a mile or so west of Postbridge was quite a nice craft pottery, and hopefully still is. The leaflet said alderwood charcoal was best for gunpowder, but what they made at the mill was for quarry blasting - not necessarily the same properties as a ballistic propellant.
Edited By Mick B1 on 22/12/2021 12:40:19
|Harry Wilkes||22/12/2021 12:41:42|
1322 forum posts
Back in the late sixties I had a apprentice who had a skill in making 'cannons' he would make them out of anything suitable he could find doing a lot in his lunch break also made his own power one lunch time he shot one at a large wooden storage cupboard and the ball bearing passed through the front and back of the cupboard once I realised the power of his device I told he could still construct them in his lunch time but never fire one at work again
|Mick B1||22/12/2021 14:16:34|
|2157 forum posts|
'Smokeless' is a bit of a relative term, like 'stainless' for steel.
Look at any photo or footage of a large 20th C warship firing its main armament, and there are always vast volumes of dense, dark smoke emitted - even though 'smokeless'propellants like nitrocellulose, cordite or their analogues were in use. In some notable sea battles, such as Falkland Islands in 1914 or the final Bismarck action in 1941, ships had to alter course in order to prevent their own gunsmoke clouding their gunnery direction.
I've never been able to find out why such copious smoke was emitted by heavy guns, when smallarms really do produce very little. One witness to the Gallipoli bombardments in WW1 blamed the silk bags in which the propellants were loaded to the guns. I even begged a bit of silk from my wife's weaving stock, and loaded it into a couple of .303 rifle cartridges to see if I got a puff of smoke when I fired them at the next range meeting, but got nowt. Anyway, the German guns, which had used big brass cases like oversized rifle rounds, smoked just as badly as the British.
Some have suggested that it's steel particles from the gun chambers and bores, washed out by the high pressures and temperatures. But the rifled liners for the big naval guns lasted about 300 - 400 rounds - say a third as many as an infantry rifle barrel at the time - so if that were so, the rifles should have still smoked a fair bit more than they did.
|Phil Whitley||22/12/2021 15:43:06|
1437 forum posts
there is a very good method of mixing and grinding black powder by rubbing between two sheets of glass, of course, this practice can also ignite the mixture, ask me how I know..................
|Mick B1||22/12/2021 16:24:59|
|2157 forum posts|
Some of the early pointed black powder filled shells used in 19th C rifled muzzle-loading guns didn't have fuzes. They relied on the friction between the powder granules on the sharp deceleration of impact to fire their bursting charge.
|Dave Halford||22/12/2021 19:09:36|
|2004 forum posts|
Battleship main guns used 6 x 100lb bags of nitro cellulose propellant LINK the link is interesting
1840 forum posts
Until quite recently I used to make my own fireworks, and lots of them. By far the most critical component is charcoal. It had to be air float quality, amything less will render the mix useless apart from making lots of smoke. You can grind it by hand but its very hard work so making it pre industrial revolution must have been very difficult. Its not hard to make a fountain which goes twenty feet in the air but i dont think the neighbours were all that impressed! Making boilers isnt half as much fun.
|vic newey||22/12/2021 19:45:16|
148 forum posts
As a one time collector of muzzle loaders I took great interest in gunpowder. In the very early days the dry ingredients were mixed together and and poured into barrels, during transport by cart the vibration used to start separating the ingredients into layers, when they arrived at their destination they were considerably weakened unless fully remixed. The answer came with corned powder which was mixed wet and and then ground up so the grains were not only uniform in size also more powerful and stable.
A big problem for muzzle loaders of all sizes but more so for hand guns was fouling inside the touch hole which had to be constantly pricked out as it rapidly became blocked up with burnt residue so you got a flash in the pan but no discharge
8469 forum posts
Never occurred to me, but Mick is right: big guns do make smoke.
Progress! This is what my 1922 copy of 'Service Chemistry' by Lewes and Brame says:
Smoke Haze from Cordite - Although nitro-glycerin and gun-cotton are both of them absolutely smokeless, yet the rapid firing of a number of guns using this powder gives rise to a fog or haze, and with the increase in charges necessitated by the introduction of modified cordite, this has shown itself to be rather troublesome and hampers the use of the guns to a certain extent. This haze, which becomes in some cases a thick yellow cloud, is due to several factors. It consists of condensed water vapour, smoke from the powder primer, vaseline, and the cartridge bag, and oxide of copper from the driving bands; and as the moisture, vaseline and cartridge bagging increase directly with the charge, this trouble necessarily increases with the use of the modified cordite.
Earlier it's explained that Mk1 Cordite was modified to reduce the burn temperature after finding British Artillery used in the Boer War soon became inaccurate due to 'rapid washing away of the bore' : the flame temperature of burning Cordite is above the melting point of steel.
M.D. Cordite is:
Tri-nitro-cellulose - 65%
Although the book doesn't say so, I'd expect any chemicals added to reduce flash would cause smoke too. Sodium Carbonate, Sodium Bicarbonate, Potassium Chloride and Rock Salt are mentioned.
Although claiming to be Tri-service, 'Service Chemistry' has a distinctly nautical flavour because it was written by Professors at the Royal Naval College, Greenwich. However, it covers a wide range of Chemistry as applied practically to Hydrogen Balloons, Batteries, Combustion, Water (for Boilers and drinking), Boiler Incrustations, Carbon (Coal, Coke, Oil, Diamond), Fuels, Ventilation, Propellants, Explosives, Iron, Steel, Non-ferrous metals, Alloys, Corrosion, and Fouling. Although a century old, much of it is still valid, and in many ways more readable than modern textbooks! They tend to plunge into hard to grasp fundamentals, more physics than chemistry. For ordinary folk, life was simpler before the nature of the chemical bond was understood!
|Mick B1||23/12/2021 19:10:33|
|2157 forum posts|
Thanks for the pointer to the book, Dave.
Reduced-flash cordite was of course of significant value for RN cruisers engaging Scharnhorst at North Cape - ships stalking and shooting by radar in the Arctic night.
|Neil Wyatt||23/12/2021 20:59:37|
18990 forum posts
A friend of my dad's warned me about playing with gunpowder when I was a boy, Despite him only having half a thumb the message didn't stick...
On the range of cannon, it wasn't Barnes Wallis who discovered armaments could skip like stones on the water.
|Mick B1||23/12/2021 21:10:20|
|2157 forum posts|
Everybody warned me about playing with gunpowder when I was a boy, and it didn't stick...
I managed to hurt myself once, luckily with no permanent effect - except to be more careful next time. That was the warning that stuck.
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