12.5 inch RML Technical Details

Some notes on the technical features of the 12.5 in 38 ton Rifled Muzzle Loaded gun from 1885, covering the mechanism in the gun carriage and fitted to the platform. The method of building the gun from wrought iron rod and constructing it using concentric coils to pre-stress the inner parts are illustrated in concept - there is no guarantee that the actual machinery used at the time bear any resemblance to that shown in the movie - concepts only. Gun design is covered briefly, concentrating on showing how internal pressure was measured using crusher gauges fitted to test guns. Finally, a method of measuring muzzle velocity is shown, and a hint given for the mathematics needed to calculate velocities at different ranges, which in turn resulted in range tables used for actual firings.
When watching this animation, bear in mind the technology available at the time. No computers , no electronics, rudimentary electrics (wet cell batteries). So measuring time (for muzzle velocity) used the known constant - gravity. Electric motors would be subject to speed variations depending on the state of the batteries. However, the level of mechanical skills were impressive. Machinery capable of finishing to an accuracy of a few thousandths of an inch on rotating masses weighing several tons were available, as were the artisans. Even more impressive was the level of mathematical skills needed to calculate the stresses that would be experienced in a gun, to determine the thickness of the coils, and the actual dimensions to be machined so that outer coils would shrink onto inner coils and so pre-stress them, while at the same time expanding sufficiently so that heated outer coil could be slipped over an inner component. Range tables were calculated laboriously by hand or with primitive calculating machines.
The other thing to note is that these guns were still using Gunpowder - an explosive. The Mark 1 gun used pebble powder - gunpowder compressed into small cubes in an attempt to slow down the explosion and so reduce the rate of gas generation. The Mark II gun would use Prismatic gunpowder, where the explosive was formed into larger prisms, slowing down the rate of burning still further but also requiring a longer barrel to ensure all the powder was burnt before the shell left the barrel.
This animation was created using Cinema 4D, Quicktime and iMovie.
Music: Modern Situations by Unicorn hHeads
References:
Handbook for the R.M.L 12.5 inch 38-ton Gun, Marks I and II, 1885
Treatise on the Manufacture of Guns and Text-Book of Service Ordnance, 1886
Treatise on the Construction and Manufacture of Ordnance in the British Service, 1877

[@JohnCBobcat]

Proof that artillery (and to a lesser extent also long-distance rifle shooting) is weaponized mathematics.

[@ronhudson3730]

Interesting take. I guess everything is applied math.

[@alexwilliamson1486]

As ex Royal Artillery, our instructors would often say “Gunnery is a science, not an art” Lots of maths involved, from the muzzle velocities, to the world spinning on its axis….many variables to be accounted for. #UBIQUE

[@seekwhen1848]

The attention to production details is nothing short of stunning really. Nothing compares to this on youtube!

[@ronhudson3730]

Agree. These are astounding.

[@Hybris51129]

Never seen how the Chronography was done in this era before so that was even more interesting to see than the gun. The gun itself is a marvel of industrial tooling and forging tech and highlights why many nations had to buy (often from the UK) things like guns and ships as they lacked the industrial capacity to make the tools needed to make the tools needed to make the guns and armor.

[@katana1430]

This is incredible, not just in the animation, but in the information it imparted. Please keep up the excellent work.

[@TheChrush3r]

best quality work as usual, glad to see you posting again!

[@xam113w]

Excellent demonstration of how a built-up gun is made

[@shanerountree3623]

While I really enjoy all of your "How it works" videos, this one that went into the details on how it's built an tested was even better! Hope you keep making them, and if you do this for fun as an hobby and take a while on completing one, that's OK. I can wait for quality ones like this!

[@vbbsmyt]

Glad you like it. If you are not already a subscriber, please subscribe and help me get to 100K subscribers.

[@ashleysmith3106]

I have often marvelled at the 10 inch 20 ton RML guns at Fort Glanville, Adelaide, South Australia, but I hadn't realised how much was going on in the manufacture of similar huge guns. It is also fascinating to learn how they were proofed and calibrated; such ingenuity for the 19th century ! Thanks for the (yet another) interesting and informative video !

[@oliabid-price4517]

Outstanding work - both the gun, and the explanations / calculations. This is the kind of material that history lessons should be using.

[@drubradley8821]

WOW... I really enjoyed all the math... MINDBLOWING... I hit the pause like 80 times, rewind like 200 times...LOL... this was just amazing to see such massive numbers on one of these large bore calibers... Thank you for taking the time to show case this info..

[@britishmuzzleloaders]

Fantastic Rob! The time to cycle such a weapon is so easily overlooked... The crews would be working hard!

[@logoseven3365]

Wow Thank you. This is so thorough, I believe I could go into my shed and build one.

[@dziban303]

Amazing work.

[@Salmon_Rush_Die]

My respect for men who did these type of things back before our high tech era.

[@kyleeames8229]

It’s amazing how in retrospect some things are seemingly obvious. They had the industrial and technical capabilities to design and build this piece of hardware, yet they didn’t breech-load it.

[@sfperalta]

Wonderful detail! I had no idea of the complexity and precision of these classic artillery pieces. Even the velocity test equipment were surprisingly sophisticated in this pre-electronic age. The animations made the whole thing super easy to understand. Well done!

[@vbbsmyt]

Thank you, could I ask you to subscribe, if you haven't already done so. Getting close to 100K.

[@brucewilliams6292]

Thank you for adding the additional information on construction techniques and the calibration procedures! :)

[@m26a1pershing7]

just when I think this guy can't get any more in depth....... answers all my questions before I even think of them

[@Skaldewolf]

Interesting how the C-coil is made from winding running in the same direction. I figured that cross-winding the layers would make for a stronger structure.

[@vbbsmyt]

You may be right.

[@SitioLumbia]

Still waiting for the Great German 88. And best quality video as always.

[@felixthecat265]

Crusher gauges were usually just dropped down the barrel. Provided they were touching the back of the breech, they would stay there during firing and were recovered after the shot. When breech loading came in, the same procedure was used with a number of crusher gauges placed around the back of the charge so they were in contact with the breech block when it closed.. Armstrong developed a system of barrel construction using steel wire or tape wound round the barrel. These allowed a thinner profile barrel to be built which was useful when turret mountings for ships were developed.

[@vbbsmyt]

I question your claim that crusher gauges were dropped loose down a barrel. The gun design documentation of the period does not mention this, and I am skeptical that the gauges would remain in the barrel after firing - so where would you find them? It is documented that crusher gauges could be inserted into the rear of a test round. However this would only record the peak pressure in the chamber, and as such would not be useful for recording the pressures at various points along the gun barrel - which would be vital for the design of the gun reinforcing. In addition, the pressures along the barrel would allow the pressure profile of the slower burning powders to be assessed. A loose crusher gauge or gauge in a shot would not be of use. I could be wrong regarding loose crusher gauges, so please let me have a reference to a contemporary document where this practice was used in the 1860 - 1900 period please.

[@felixthecat265]

@@vbbsmyt I will see what I can do. You need to understand that the research that was carried out in the 19th C was not on the same basis as modern research by government agencies. Loose crusher gauges were used by Artillery officers to monitor powder performance. The concept of test barrels drilled for pressure gauges came later.

[@lyedavide]

Amazing video with so much information! Beautiful rendering. Probably the best video on the subject on KZbin.

[@guillaumeroncin5870]

Thank you so much Robert. CGI is stunning. Historical, technical and industrial informations are really interesting..

[@martkbanjoboy8853]

Thank you for removing some of the mystery of York Redoubt fortifications through your beautiful animations. Armstrong guns have fascinated me since I first laid eyes on them when I was a boy of eight years. As far as I know York Redoubt is one of the few locations with these guns in the whole continent in any state of preservation.

[@gvii]

That is really interesting. Especially the chamber pressure and velocity measurement methods. Very cool stuff.

[@iceman7975]

Another quality video and graphics. Excellent as always,well done. These were abundant in Gibraltar and a fair amount of barrels some on their mounts still exist,although unfortunately we don't have the complete package.

[@neilfurby555]

Extraordinary work, thank you.

[@norbert0320]

Excellent job my friend, thanks!

[@CRISTIAN-th7jr]

Saludos estoy muy sorprendido por el espectacular trabajo que han realizado es una obra de arte, incomparable. Los felicito y aplaudo de pie su trabajo.🎉

[@polymathart]

I’d love to see an animation of several guns in a fort in action, differently timed, all firing at selected targets.

[@huseyincanercan4132]

Thansk a lot for the building steps. I`m from Canakkale/Gallipoli and we have several historic guns from the WW1, even we have a monument piece at the main square. I belive they have produced by Krupp factories. I was always curious about their production.

[@irisandxxx5003]

Thank you, A MASTERCLASS VIDEO !!

[@FRIEND_711]

I know these must take quite a while to make and i really appreciate your hard work that you put into this. Do you think you can make a video doing the Skoda M1909?

[@snizami]

Often fascinating, after watching how much work would go into making these weapons, to go and read that they never really saw actual use. They had to be made for deterrence or posturing or what have you, but still...

[@MM22966]

Very neat stuff! I read David Weber scifi books, and they talk about recreating a lot of this technology, but I never had a working visual referent before.

[@DABrock-author]

Yep, the Safehold series. Wish he would get the next one out. I need to know what’s up with the orbital platform and the return of the saints.

[@MM22966]

@@DABrock-author I don't think he's going to finish it. It wandered all over the place the last, what, three books? I got the feeling he was bored with it.

[@DABrock-author]

@@MM22966 I was afraid of that. Oh well, since I started writing and publishing my own stuff, I don’t have much time to read other books anyway. 🤓

[@51WCDodge]

Beutiful presentation, the technical illustrations and explinations are clear and consise. Learnt a lot from this. Thanks!

[@timtank3669]

Awesome job! Thank you, Sir! ❤

[@ilike8590]

Amazing stuff. Unfortunate that this sort of stuff doesn't rack up much views though with something as niche as Victorian artillery and Ironclads, I suppose that's an given.

[@gaston01000]

Nice Job man. The next time, do one about of the Ross Rifle. Greetings

[@BLECHHAUS]

Another fantastic work! Thnx for sharing :-)

[@mikeevans96]

The chronometer amazed me.

[@ronhudson3730]

For the feeble-minded (me) perhaps an accompanying explanatory VO?

[@AspiringSteampunk]

Probably the most understandable presentation of the British RML guns on the internet, and definitely your most educational work to date. Well done! Though, with all of the mechanical assistance designed into the carriage, I have to wonder why they went with almost pure manpower for the loading process? I suppose in fortress applications manpower would be somewhat less of a concern than at sea.

[@vbbsmyt]

The big difference is, at sea, guns always had steam available to power hydraulic systems for loading, training and hoists. Ashore, I presume, it would not economical to fit boilers, steam engines and the hydraulic pipe work, along with the trained artificers to maintain them, on the off-chance that the country would be invaded. Far better to have lots of strong gunners. My animation of the 100-ton gun in Malta shows the sort of machinery that would be needed.

[@Sailingspeedat9kn]

Hi could you please make a video about the RSC model of 1917 and or a video about the Winchester lee navy that would be awesome I love your videos these are some of the best you can find on the internet I know that these are super complicated to make

[@XMarkxyz]

Al the building, proofing, testing, process is extremely fascinating; where do you even start to find somthing like a Victorian instrument to mesure muzzle velocity?

[@51WCDodge]

Used to be at The Woolwhich Aresenal London. Guns like this , due to the range they could shoot, were then shipped to Sheerness proof range. A lot of the old Arsenal buildings remain, though now housing and offices etc. when the Arsenal finally closed there was a lot of technical archive still there. Don't know where it has ended up. A lot of equipment was sold for scrap or export to other countries. the Arsenal had its own railways, barges , tugs and launches for transporting finished guns. The Fleet even had its own Blue ensign. The flag flown by British vessels that either, are part of an official Goverment Service, or an Organisation, or person, granted the right by Royal Warrant.

[@vbbsmyt]

Thank you. The references I used are given in the video notes, and can be downloaded from the web. It is a pity more stuff from the Arsenal was not saved. Rob

[@robertcornelius3514]

"It's not the barrel of a cannon that worries me, but the improvement in the shell." - Albert Einstein

[@acebacker1]

Wonderful work thank you

[@davidbrennan660]

Fascinating.

[@garyneilson1833]

Fascinating video, it engineers building it must have been good to get to 5 microns with the tooling they had then

[@garygenerous8982]

Amazing video with so many little things I’d only ever read about brought to life to see. You blew it out of the water like usual sir. One question, I have heard of a “Ballistic Pendulum” for determining muzzle velocity in old cannon but never seen it demonstrated so would that last segment be an updated version of that concept or are they measuring completely different aspects? Thank you again for the wonderful video and I can’t wait to see what you show us next.

[@vbbsmyt]

The Ballistic pendulum relies on a heavy pendulum capturing a bullet, and measuring how far the pendulum rotates after the collision. The kinetic energy of the bullet is converted into potential energy of the pendulum/bullet - how high the pendulum block has risen when it rotates. There is no need to measure time. There is a very good KZbin video explaining this. (Ballistic Pendulum Physics Problem) A ballistic pendulum is, therefore, usable for small arms and small cannon. However if firing, say, a 110 pound (50 kg) shell, you would need a VERY large pendulum (or more likely a pair of pendulums, the first to slow down the shell and second to capture it).

[@marklatimer7333]

Excellent Animated Presentation, I look forward to your videos and always learn something. The copper disc pressure measuring procedure is fascinating, I assume drilling multiple holes along the length of the barrel was only done on the prototype barrel for testing purposes?

[@katana1430]

Usually yes. the is the origin of Copper Units of Pressure which can still be found in some firearms reloading manuals.

[@user-li4wq2qg2b]

Очень интересно. Но самое интересное - как в то время производили измерения давления в стволе и скорости снаряда (такие подробности редко показывают).

[@MM22966]

Kind of funny how they got to adding the breech piece, but nobody was yet at the point of "Hey, why don't we just make it loadable from the rear as(s) long we're doing this." Was it because the gun was so heavy, they didn't have the confidence of designing a breech that would stand up to the firing pressure yet?

[@vbbsmyt]

Basically, yes. But by the 1890’s, better quality steel, cordite and the Welin breech had been developed, and Rifled Muzzle Loaded guns became obsolete.

[@MM22966]

@@vbbsmyt Well, thank you for doing these. They are fascinating visual history.

[@DRIZZLERE17]

I would have assumed that the barrel should have already burst because of the 16 test holes that were drilled all the way through.🙂

[@jakubr3831]

5 microns? impressive, it is more like cnc today

[@metaname1]

Автор потрясающе внимателен к деталям. А вообще, есть что-то очень печальное в том факте, что вплоть до конца 20-го века, самые квалифицированные инженеры и ученые занимались изобретением орудий уничтожения людей, а не того что было бы полезно для обычных граждан. Всем добра и мирного неба.

[@JO-ch3el]

I'm wondering if they pre-drilled the holes where the crusher gauges were inserted and was it done on every gun? Also how would they retrieve gauges after firing?

[@vbbsmyt]

Crusher gauges would only be fitted to test guns, never to operational guns. The crusher gauge inserts were unscrewed from the test guns after firing, and the copper cylinders then removed from the insert.

[@HYEOL]

Incredible

[@R.TKryoman]

How to cut rifling?

[@keithmoore5306]

ah you made a mistake there, black powder doesn't exploded!! it merely burns at a vastly accelerated rate! i always did wonder about how they did velocity back then! if you take requests, could you do battleship gun base fuses? i can't find anything on how they operate (as in not detonating on firing!!) or where and how they're mounted in the shell?

[@vbbsmyt]

You are confusing Explode with Detonate. Gun powder is a (low) explosive that deflagrates (flame front moving through the substance less than speed of sound) while High Explosives are detonated by a supersonic shock wave. So Gunpowder is an explosive that explodes.

[@Chironex_Fleckeri]

I get what you're saying but the difference is between what happens in a tube and in a shell, simply put. Low v. High is a distinction made by humans. It isn't best practice to discuss specifics around the ordnance because yeah... but I think you're referring to the invention by Nobel. Something with an aromatic ring and two naming conventions. Chemists still debate where it starts. You're crossing scientific with historical in the comment but it is true these old naval guns didn't have the oomph of modern propellant charges use. That didn't make them any less useful. They are just outdated and outclassed in a military sense but nonetheless were extremely effective in influential in their historical context.

[@keithmoore5306]

@@vbbsmyt a deflagration is not an explosion an explosion doesn't leave a residue behind like gunpowder does! an explosive doesn't leave a residue behind that will interfere with any operations, while the speed of combustion in a deflagration can be described as an explosion chemically it isn't, chemically to qualify as an explosion molecular bonds in the material have to be broken in the reaction. interestingly not all explosives are explosive! ANFO for example really just deflagrates like gunpowder does!!

[@Sir_Uncle_Ned]

If you’re going to do that to the ring, at least take it out to dinner first!

[@thecaptainindustrialsales4560]

5 micron is 0.00020" not 0.0001 as you state

[@nowhow4853]

ПОКАЗАНО ЗДОРОВО. ВСЕ ДЕТАЛЬНО.

[@sebastianthomsen2225]

😎👍👍

[@LuciusQuinctiusCincinnatus111]

👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍

[@bighead6106]

东莞虎门沙角炮台有一个，清政府找德国人买的

[@LuciusQuinctiusCincinnatus111]

CSS H. L. Hunley 🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏

[@dylanp.5161]

125% not 1.25%

[@vbbsmyt]

A fair cop - yes it should be 125%.

[@picardbs]

Anyone sitll thinking they didn't have 'techonology" in the 19th century?