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Henry O.





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PostPosted: Sun 23 Sep, 2018 2:30 pm    Post subject:         Reply with quote

Jean Henri Chandler wrote:
Also if his was so 'overclocked' as you say it would seem to have been an insane risk on his part to shoot the centuries old antique!


Well. . . presumably he wasn't thinking about that at the time Razz

What I was thinking is that if Gallwey really was just really lucky and happened to get his hands on some examples of a really "delicate" style of crossbow which didin't usually survive 400 years and thus doesn't show up in museums very often, that might help explain a lot of the problems Tod is running into.

Tod said earlier in this thread that examples of medieval crossbow typically have a cross-section ratio of around 3:1 or 5:1, which is a big part of the reason they seem to have such a sluggish cast. The steel bow of Payne Gallway's siege crossbow however was 2.5 inches wide and 1 inch thick at the center for a ratio of 2.5:1 (and we have no idea what the dimensions were near the tips). The steel military crossbow he says could shoot a bolt 390 yards was, in the center 1.75 inches wide and 0.75 inches thick for a ratio of 2.33:1 (and again, we don't know what the dimensions were near the tips).

I don't know if tod has tried making steel crossbows that thick before?

Henry,
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Jean Henri Chandler




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PostPosted: Sun 23 Sep, 2018 4:53 pm    Post subject:         Reply with quote

Henry O. wrote:

Even for a company of mercenary foot crossbowmen that are all equally trained, it would have still been best to have a diverse mix of different sized windlass crossbows, one foot crossbows, two foot crossbows, etc. The heavier crossbows could be used to conduct long-range harrassment or to aim at specific, high value targets while the lighter, quicker-firing crossbows keep shooting to cover the heavy crossbows as they reload and to pick off all those annoying longbowmen that keep trying to approach.


All interesting theories but I don't think you have to guess so much. Look into it you'll start to find the real patterns of what they actually did and didn't do.

As far as I'd read, at least for Central and North Eastern Europe - using the windlass spanned crossbows in the field had become fairly rare by the 15th Century.

The two types used in the field by towns, royal armies, Hussite Armies, and groups like the Teutonic Order, were basically the 'medium' powered the stirrup crossbow, and the more powerful cranequin crossbows. The former were cheaper and could be made more quickly, the latter were more expensive and also required the cranequin device, but were of course more effective.


Quote:

Regarding the ranges you give for medium-power crossbows and arbalests, can you give examples of some of the sources that's based on? It would really help a lot.

Henry,



I think I've posted a link to this article before in this thread. It's a useful summary for late medieval crossbows derived from the records of the Teutonic Order.

http://deremilitari.org/2014/03/horses-and-cr...n-prussia/

Among other useful things he enumerates the numbers of types of each types of crossbow they had on hand and were producing (and for example how many of each type of prod they ordered and how many bolts (a lot!) and so forth.

I think his source for those ranges which I quoted was from this article, E. Harmuth, Die Armbrust. Ein Handbuch (Graz, 1986), pp. 199-200.

The primary sources for most of what is in that article are the various chronicles associated with the Teutonic and Livonian Knights, many of which were transcribed and published (mostly in German only) in the 19th Century. Some of the main complete ones easily available today include:

Chronicle of Henry of Livonia (13th Century)
Livonian Rhymed Chronicle (14th Century)
Chronicon Terrae Prussiae Peter of Dusburg, (14th Century)
Elbing-Preußisches Wörterbuch (14th Century)

And there are a ton of partial translations of other later chronicles in various academic articles. Some of these are summarized in the two English language histories of the Teutonic Knights, William Urban's Teutonic Knights: A Military History and Eric Christiansens The Northern Crusades.

(There is also some interesting stuff in some of the Osprey books but they rarely give their sources so you have to take that with a grain of salt.)

I found the Balthazar Behem Codex Picturatus (late 15th / early 16th Century) useful as it includes guild regulations related to the militia including the crossbows. It includes images of practicing shooting the popinjay with crossbows too.

Another good primary source are the chronicle of Henry Bolingbroke, Earl of Derby, later King Henry IV of England, who made two Crusades to the Baltic in the years 1390-1391 and 1392. He participated in the siege of Vilnius and was engaged with the Lithuanians (and their various Latin / Christian allies) on behalf of the Teutonic Knights, he also brought a few hundred English longbowmen with him so you do see direct conflict between the two weapon systems. His journal is available online. Unfortunately it's in Latin and so far as I know hasn't yet been translated into English (if anyone knows otherwise let me know). I have had friends translate a few small sections for my own research but they are rough translations.

Christine de Pisan's war book is a great source (it mostly chronicles everything you need for a siege of a castle garissoned by 300 soldiers - which is a staggering amount of stuff including over a million crossbow bolts)

The famous Schloss Wolfegg housebook and the Mester van het Hausbuch both feature crossbow hunting and details on warfare with mounted and infantry crossbowmen.

Several Late medieval war manuals also get into this stuff including Conrad Keysers Bellifortis, Johannes Bengedans Kreigkunst und Kanonen, Philipp Monch's Kriegsbuch, and the Ludwig von Eyb Kriegsbuch, as well as the three by Johannes Hartlieb.

I also have the Lübeck, Hamburg and Bremen chronicles (which are available in a summarized translation in English and are also available online as direct transcriptions from the 19th Century, in Low German) and I have a copy of the Nuremberg Chronicle with an excellent accompanying handbook. I have some translations from it available.

The various Bohemian chronicles and accounts of the Hussite wars, which are too numerous to list here.

And then the are the Magisterial academic histories by Jan Dlugosz (which to me is the best history book I own by a wide margin) and he occasionally gets into the nitty gritty details of battles, Piccolomini - in particular his history of Bohemia, and Machiavelli all talk about them.

For modern histories I also particularly like Johannes Janssens Geschichte des deutschen Volkes seit dem Ausgang des Mittelalters (which is available in English), as he gets into a lot of detail on the urban life including the shooting contests and quotes a lot of translated passages and Philippe Dollinger's Die Hanse (which you can find in French and English) which also has a bunch of transcribed or translated records and is a great source for any kind of naval warfare in the Baltic. And Hans Delbruck of course.

Much more recently Anne Tlusty's Martial Ethic in Early Modern Germany gets into a good amount of detail into shooting contests. She also has several books of translations of records from Augsburg and Nordlingen and a couple of smaller towns.

Jean

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Henry O.





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PostPosted: Sun 23 Sep, 2018 11:23 pm    Post subject:         Reply with quote

Thanks Jean! I'm slowly trying to work my way through it but this is great stuff!

Henry,
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Jean Henri Chandler




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PostPosted: Mon 24 Sep, 2018 7:42 am    Post subject:         Reply with quote

A couple more things on sources...

There is this Austrian "poet" named Peter Suchenwirt who described a whole Teutonic Orders reysa or raid from beginning to end, including both some astonishing cruelty and some quite serious peril, where you can see how they could easily get in trouble (extended periods where they were stuck in mud up to their horses saddles etc.). You can find this online but I can't remember where I got it.

There is another good "popular history" article called “Towns and Defense in Later Medieval Germany”, Nottingham Medieval Studies v. 33. (1989) with David Eltis

The Henry IV thing is called:

Expeditions to Prussia and the Holy Land, Made by Henry Earl of Derby (afterwards King Henry IV) in the years 1390-1 and 1392-3 Being The Accounts kept by his Treasurer during two years Edited from the originals by Lucy Toulmin Smith, printed for the Royal Camden Society M.DCC.XCIV (1894) (English introduction and preface, the rest is Latin)

Some other modern books from Poland in particular have good data from both historical records and archeological sources, notably:

Arms and Armor in the Medieval Teutonic Order’s State in Prussia, Andrzej Nowakowski, Oficyna Naukowa MS, (Poland),
(1994), ISBN 83-85874-01-1

and

Uzbrojenie w Polsce średniowiecznej 1350-1450 (Arms and Armor in Medieval Poland 1350-1450), Andrzej Nadolski (1990)

There is also a ton of archeology which is very useful, scattered around in different journals but one of the better ones I found was the multidisciplinary Lübecker Kolloquium zur Stadtarchaologie im Hanseraum, Volumes I-IV (many of the articles are in English). But you need to spend some time on JSTOR to track a decent cross-section down

They have done some archeological surveys where they have actually tracked the course of battles specifically by finding crossbow bolt-heads with metal detectors in the ground and still sometimes stuck in trees.

J

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Jean Henri Chandler




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PostPosted: Mon 24 Sep, 2018 10:38 am    Post subject:         Reply with quote

So I watched that video again and paid a bit more attention, and I noticed the list of 'ingredients' of the pavise. Quite fascinating. Translating i have

A base of "pinewood"

with various layers including a sort of paste (the stuff that looked like cement) made of collagen fibers, iron dust, glass particles, and bone-meal, then a layer of rawhide pieces and gesso, paint and sheet metal (brass? gold leaf?)

I don't know what kriedegrund or Rotfassung are, can somebody explain?

Apparently this is derived from an analysis of an antique in the Beyerisches Nationalmuseum Munchen.

The reconstruction mentions wood, "tendons", rawhide, gesso, and gold leaf, as well as glass particles, iron filings, bone meal, Chalk / gypsum / rye flour

And something called "Fassung"?

And another thing called "Hauteim"?

Then a layer of beaten rawhide.

So with all that, I think it makes some sense how these things could stop high velocity crossbow bolts and even bullets at longer ranges. Fascinating stuff.

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Jean Henri Chandler




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PostPosted: Tue 25 Sep, 2018 10:50 am    Post subject:         Reply with quote

By the way, speaking of sources on Crossbows, the Livonian Rhymed Chronicles tell us the story (or legend) of when and how the Lithuanians acquired the secret of crossbows from a renegade marksman named berthold

https://deremilitari.org/2016/09/descriptions-of-warfare-in-the-rhyme-chronicle-of-livonia/

The following summer, the Semgallians agreed to attack Terwetein. The said castle was located in their land. It happened on a day which had been previously agreed upon. In the settlement before the castle walls nothing which could be called Christian survived, being captured or slain. A dishonorable man called Bertold was there, the Semgallians liked him because he was a bowman, he became useful to them. If he would come over to them, they would spare his life. He did this and was glad. In a short while the Semgallians found plenty of crossbows and arrows in the dwellings outside the castle. Very swiftly they gathered them together. They were glad about the crossbows. The renegade Christian then took as many archers as there were crossbows. All those who did not know how to use them he began to teach to bend and to shoot. Because of this they let him live. Meanwhile the good Brothers had defended the inner castle in various ways. They intended to guard it and keep it in their hands. At that time an army attacked from all sides.

J

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Sean Manning




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PostPosted: Wed 26 Sep, 2018 2:45 am    Post subject:         Reply with quote

Jean Henri Chandler wrote:
So I watched that video again and paid a bit more attention, and I noticed the list of 'ingredients' of the pavise. Quite fascinating. Translating i have

A base of "pinewood"

with various layers including a sort of paste (the stuff that looked like cement) made of collagen fibers, iron dust, glass particles, and bone-meal, then a layer of rawhide pieces and gesso, paint and sheet metal (brass? gold leaf?)

I don't know what kriedegrund or Rotfassung are, can somebody explain?

Apparently this is derived from an analysis of an antique in the Beyerisches Nationalmuseum Munchen.

The reconstruction mentions wood, "tendons", rawhide, gesso, and gold leaf, as well as glass particles, iron filings, bone meal, Chalk / gypsum / rye flour

And something called "Fassung"?

And another thing called "Hauteim"?

Then a layer of beaten rawhide.

So with all that, I think it makes some sense how these things could stop high velocity crossbow bolts and even bullets at longer ranges. Fascinating stuff.

Hi Jean,

Kreide is chalk (including the kind which tailors use, so you would need to talk to them to make sure they mean calcium carbonate). I am not sure what Fassung means in a craft context. Hautleim is skin glue. There is good information about slightly earlier European shields in Jan Kohnmorgen's book.

I am glad you still have time for your 15th/16th century research!

www.bookandsword.com
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Jean Henri Chandler




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PostPosted: Wed 26 Sep, 2018 7:39 am    Post subject:         Reply with quote

Sean,

Thank you and once again, thank you.

Jean

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Leo Todeschini
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PostPosted: Wed 26 Sep, 2018 1:02 pm    Post subject:         Reply with quote

Jean Henri Chandler wrote
Quote:
I think in other words we just haven't had enough iterations or a large enough community with a need for military grade type late medieval crossbow replicas to move this along faster.


Thanks for all the info and the very considered reply, I simply don't have the time right now to respond in any depth, but you are certainly right that we need more people working at it.

Liebel calculated (yes I know, calculated) an expected range of around 260yds....

Benjamin Abbot wrote
Quote:
The weight of the period evidence I'm familiar with indicates that crossbows spanned by the belt or whatnot should hit at least as hard as English warbows, assuming similar strength of the shooter,


I can't see this. A longbow will have a power stroke of around 25", a crossbow as described around 5.5", so a ratio of 4.5:1 and a longbow is say 140lbs and a belt spanned crossbow cannot reasonably be more than 300lbs for a very experienced archer, so a ratio of 2:1. This immediately says to me that a belt spanned crossbow will come nowhere near a longbow.....

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Henry O.





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PostPosted: Wed 26 Sep, 2018 4:11 pm    Post subject:         Reply with quote

Leo Todeschini wrote:


I can't see this. A longbow will have a power stroke of around 25", a crossbow as described around 5.5", so a ratio of 4.5:1 and a longbow is say 140lbs and a belt spanned crossbow cannot reasonably be more than 300lbs for a very experienced archer, so a ratio of 2:1. This immediately says to me that a belt spanned crossbow will come nowhere near a longbow.....

Regards



Tod


When you say "reasonably" is that assuming that the guy pulling the belt hook crossbow has as much extra leg muscle as the guy pulling a 140lb longbow has extra arm muscle?

Regarding the longbow, while not from me there's a post by a user named Hergrim on r/AskHistorians which talks about some of the shifting opinions about the mary rose estimates quoted in "the Great Warbow"

agincourt_a_character/drxtwb5/" target="_blank" class="postlink">https://np.reddit.com/r/AskHistorians/comments/7mu6z2/in_bernard_cornwells_agincourt_a_character/drxtwb5/

imo an average draw weight closer to 100-120 lbs better fits the longbow ranges usually quoted by Elizabethan military authors, many of whom were living at the time the Mary Rose sank: an expected average of ~180-200 yards with livery bows and arrows, up to 240-280 yards if shooting light shafts, and up to 320-360 yards if shooting gaming bows and straight-feathered flight arrows.

It also helps explain why most of the writers during this period who complain about the "decay" of English archery keep referring back to the days of Edward III and Henry V, long before they were born, and rarely seem to ever bring up "hey, remember some 20-30 years ago when there used to be a whole bunch of big, burly english archers walking around with arms the size of tree trunks? Whatever happened to them?"

Henry,
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Jean Henri Chandler




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PostPosted: Thu 27 Sep, 2018 8:23 am    Post subject:         Reply with quote

Leo Todeschini wrote:
Jean Henri Chandler wrote
Quote:
I think in other words we just haven't had enough iterations or a large enough community with a need for military grade type late medieval crossbow replicas to move this along faster.


Thanks for all the info and the very considered reply, I simply don't have the time right now to respond in any depth, but you are certainly right that we need more people working at it.

Liebel calculated (yes I know, calculated) an expected range of around 260yds....


Calculated a range for which weapon? One of Bichlers hornbow replicas from the last two videos?

Quote:


Regards


Tod


Understood Tod, I know you have a full plate.

Speaking of Bichlers crossbows, I was thinking of you when I saw this beautiful self spanning crossbow. Not a beast like the last two but certainly a nice cavalry weapon!

https://www.youtube.com/watch?v=kXli68FbqTE

the idea is from a 1505 manual called Codex Löffelholz from Krakow, same year and city incidentally as the fascinating Balthasar Behem Codex Picturatus



here is a wonderful blog where they reproduced several of the mysterious tools from the manuals, you see similar ones in the Ludwig von Eyb manual and many other kriegsbucher

http://thomasguild.blogspot.com/2016/08/the-t...-1505.html

I remember you had done some exquisite ballestrini / crossbow "pistols" and some other similar weapons, couldn't recall if you had ever done one of these, anyway I thought you would find it interesting.

Jean

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PostPosted: Fri 28 Sep, 2018 6:55 pm    Post subject:         Reply with quote

Quote:
I can't see this. A longbow will have a power stroke of around 25", a crossbow as described around 5.5", so a ratio of 4.5:1 and a longbow is say 140lbs and a belt spanned crossbow cannot reasonably be more than 300lbs for a very experienced archer, so a ratio of 2:1. This immediately says to me that a belt spanned crossbow will come nowhere near a longbow.....


Have there been any serious tests with early 15th-century-style belt-spanned crossbows? Do we know that the crossbows Pero Niño and company were using had power strokes of only 5.5 inches? What's the evidence that 300lbs is the limit? There's a video of you spanning a 350lb crossbow from the belt.

In El Victorial, spanning heavy crossbows from the belt is one of Pero Niño's feats of strength. I bet skilled crossbowers in this style were just as developed as skilled archers. I doubt we'll really get a sense the performance of such weapons until we get a bunch of folks who take crossbows as seriously as many folks now take yew warbows.

The idea that crossbows don't rely on strength only applies, if at all, to certain crossbow designs. Many of the military crossbows, even into the 15th century, required strength to operate effectively, just like a hand-drawn bow.
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Michael P. Smith




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PostPosted: Sun 09 Jun, 2019 8:10 am    Post subject:         Reply with quote

Anything new on this front recently? I’m expecting my bow from Tod shortly, and I am super-excited, and literally just read every post in this thread.... it’s gold.
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PostPosted: Mon 10 Jun, 2019 9:35 am    Post subject:         Reply with quote

Jean Henri Chandler wrote:
Ok I'll try to prime the pump.

https://www.youtube.com/watch?v=G2Rl9DLUfao

here is another very interesting test from the same people, using a smaller (but also 1200 lb draw) crossbow, spanned by a cranequin, targeting pavise shields -

the beginning of the video shows an antique pavise with some damage from crossbow bolt heads, then they show some examples of how the replica was made in various layers of I am not sure what, then they shot it twice and compared the damage to the original.

Bolt 1

81.3 grams, 358 mm / 14" long (speed 69.3 m/s) penetrated 32mm (1.2 inches)

Bolt 2

81.1 g, 359 mm long (speed 69.85 m/s) penetrated 32mm (and lost a feather)

This is close to 200 joules. In the comments he mentions it's a 190mm powerstroke (7.4 inches)

Again by comparison a very powerful (144 lbs draw) English longbow reaches 160 joules so this is giving us performance clearly superior to the longbow (or most modern crossbow replicas) and a bit closer to what we would expect based on period sources or the famous Payne -Gallwey test.

J


I would say the guy who did these tests linked above, whose name appears to be Andreas Bichler, is the furthest along in the development of Late Medieval / Early modern type crossbows in terms of performance. 69 m/s is close to the power levels we would expect based on medieval records. He appears to be an academic, but I don't know the right people in Austria to make contact with this person, he may not necessarily want to engage in public anyway.

I could check with some of my HEMA friends over there though and see if any of them have the right connections.

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PostPosted: Mon 10 Jun, 2019 1:04 pm    Post subject:         Reply with quote

Just FYI, and because there was some confusion about a couple of ingredients mentioned for the pavise repro above, Kreidegrund is a primer/undercoat used (often, not always as far as I know ) in Medieval woodcarving to prime the sculpture for painting/gilding etc. I believe, it consists of the above-mentioned 'chalk' suspended in some form of animal glue.

It could also be applied to hide mistakes, or add details, that would have been too difficult or time consuming to carve (say, for example, veins on exposed parts of the body. These might be achieved by covering strips of leather, parchment, rope &c. glued to the wood, then painted).

Gefasste wooden sculpture generally means the wood is not visible anymore, i. e. has been painted/gilded. So, in this case, Rotfassung either alludes to a layer of paint or primer for gilding, or both. So, if I am not mistaken, we can translate Fassung variously as 'finish', 'coat of paint' or even 'undercoat'.

It would, of course, be great, if an actual art historian could check that I haven't committed any serious blunders here...

- Michael
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PostPosted: Mon 10 Jun, 2019 9:01 pm    Post subject:         Reply with quote

Bichler’s work in composite crossbows is fascinating. I think he has probably had the greatest success in replicating such a crossbow. Just from a materials point of view, I’d expect such a prod to be more efficient than a steel one, though obviously steel has some advantage in not being subject to as much change due to weather, and steel will, of course, be much more durable.

With regards to steel prods, I think in general they are more practical for those of us wanting a reasonably representative modern replica, even losing some pound-for-pound efficiency. But if money were no object, I’d certainly be interested in funding more composite replicas!

The first five years of my career was in a steel alloys materials lab. I tested a lot of springs and turbine fan blades!
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PostPosted: Mon 10 Jun, 2019 9:39 pm    Post subject:         Reply with quote

Based on what I have seen in period records, the steel and composite prod weapons of equivalent 'rating' were considered to be basically the same in terms of effectiveness. For example they were interchangeable in the German Schützenfest, the only categories were apparently by size and the type of spanning method. A "Halbe Rüstung" crossbow could have either a steel or composite prod.

The only distinction I have seen is that the composite prod weapons were considered to be better in the winter or extreme cold. The steel prod weapons were at greater risk of snapping in very cold weather (snapping was always a potential danger with military grade crossbows). Conversely, they believed the composite prod crossbows worked better in extreme cold, as in they actually got stronger. For this reason the Teutonic Order preferred the composite prod type for their more powerful rated weapons. On the other hand in warmer weather there is also anecdotal evidence that prods could be damaged by rain, supposedly this happened to Genoese mercenaries in French service on a couple of occasions.

Other than that the only difference is that the steel prod ones were apparently significantly cheaper to make. Cost in some markets was 1 mark vs. 3-5 marks for the equivalent grade crossbow with a composite prod.

The x-ray of one composite crossbow prod showed a layer of wood, with 7 layers of horn over, and then a layer of "tendon" over that, and then a final layer of birch bark purportedly as a waterproofing measure. I have read that they specifically used the nuchal ligament - the ligamentum nuchae - of a horse, which is the tissue that keeps a horses head up. Horses apparently don't make any effort to keep their head up, they have to flex muscles to make it go down like to drink water or eat grass. That tissue is very elastic and strong and is part of the secret of the composite prod or hornbow. At least, this is what I read.

If you have ever seen these things in a museum the (composite) prods can be very thick, the one at the Higgins armoury had a prod almost as thick as my forearm and I've seen others like that in Switzerland and Germany.



Bichler is definitely on to something, I remember reading a paper about a test just a few years ago (I think maybe linked in this thread a few pages back) resulted in three weapons basically de-laminating after just a couple of shots. Getting all those materials to stick together properly can't be easy. Bichler seems to have figured that out.

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PostPosted: Wed 12 Jun, 2019 9:16 am    Post subject:         Reply with quote

I have seen composite bows, though mostly of slightly later period (16th & 17th c). Steel will be less efficient just because of mass density, if nothing else. The steel prod will have a higher moment of inertia.

From a materials point of view, the modern steel prods are no doubt better than their medieval counterparts (I am, of course, speaking to replicas which are reasonably faithful in dimension). Although the alloy selected and the quality of heat treat can have a huge effect on the yield point (beyond which we get plastic deformation or fracture), there is remarkably little variation in the elastic modulus of carbon steels (mebbe 5% variation around 200 GPa?). Not much chance in finding more performance in the prod, IMO. That leaves other possible efficiency bandits..... geometry and maybe the bow string seem like the only possible avenues for major improvements. Geometry is something we can evaluate pretty readily, but I don’t know the sensitivity of system to small variations in geometry. Same with bowstring. Can a very small unexpected stretch cause a significant loss of efficiency?
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Bartek Strojek




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PostPosted: Wed 12 Jun, 2019 9:44 am    Post subject:         Reply with quote

I think that Egon Harmuth had stated in "Die Armbrust" that about 45% efficiency is about the most you can get out of steel bow. So about 45% of energy 'stored' in a bent bow is being transferred to an arrow.

With selfbows using heavier arrows, you can get well above 80, while Adam Karpowicz was getting up to 95% with his Turkish reflexive bows.

http://www.atarn.org/islamic/akarpowicz/turkish_bow_tests.htm

Now the question is where could composite prods fit into this....
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PostPosted: Thu 13 Jun, 2019 7:03 am    Post subject:         Reply with quote

Bartek Strojek wrote:
I think that Egon Harmuth had stated in "Die Armbrust" that about 45% efficiency is about the most you can get out of steel bow. So about 45% of energy 'stored' in a bent bow is being transferred to an arrow.

With selfbows using heavier arrows, you can get well above 80, while Adam Karpowicz was getting up to 95% with his Turkish reflexive bows.

http://www.atarn.org/islamic/akarpowicz/turkish_bow_tests.htm

Now the question is where could composite prods fit into this....


Didn't Tod get something over 50% with one of his stee crossbows firing a heavy bolt some years ago?

I remember the efficiency being higher than that of Mark Stretton's longbow
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