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Thread: English Longbows w/ No Penetration?

  1. #61
    Ichon's Avatar Praeses
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    Default Re: English Longbows w/ No Penetration?

    The maths seem to be correct though when I enter it into archery calculator I am getting quite a bit lower joules so I'll have to double check if there is an error in your maths or how I am using the calculator.

    A few issues with assumptions on the inputs is my main critique. Firstly 10 degrees is fairly shallow but most important the assumption of only 5 joules lost energy per 10 meters. That is probably about right for modern vaned arrows but all the tests I've seen on authentically feathered longbow arrows have quite a bit more slowing due to the much higher drag. Also 64 gram arrows at 63 meters per second is a bit high. Not outside the realm of possibility but would probably require 180+ lb draw and that is the upper range of weight for the arrow and getting close to the best case scenario especially considering slightly pulled release will greatly affect results at any range past 40 meters which for most battles that English archers participated in would be just a bit beyond point blank range.

    The final issue is something I'm not sure of the maths behind but angle of impact doesn't quite describe hitting a rounded surface vs a flat angled surface with a broad point that is likely to be off straight hit both by vertical and horizontal axis.

    I do believe some arrows could penetrate lower quality plate but mostly at closer ranges and even then not reliably though if several bowmen aim at the same person some arrow could probably be effective enough to kill at ranges less than 20 meters. Descriptions of Agincourt mention 800 men at arms approaching on foot and wearing presumably poor quality plate making it to within 60 yards of the English before significant casualties and around 200 men closed to melee. The other 600 are described as wounded or dying but losing 600 men crossing only 60 yards is severe casualties. However they were thrown into disorder by the retreat of some French cavalry, coming up a slight hill over very muddy ground. Even if trying to move fast probably were close to a normal walking pace and would take 40-60 seconds to cross that distance giving the English 4-5 volleys from a couple thousand archers or roughly 10,000 arrows vs 800 men.

  2. #62

    Default Re: English Longbows w/ No Penetration?

    My calculations are not incorrect. Trust me! 0.5mv^2 is the formula for kinetic energy. If you know the velocity and weight you also know the KE.

    Warbow arrows have long and low fletchings as stated by Iolo Goch, and this will minimize drag.

    63 m/s for a 64 gram arrow is the accepted velocity with a 170 lbs bow. The reason I used this in my previous post has to do with the data I have on a small square-heads, and in the test conducted by Alan Williams he used a square-head of the size you'll find on a 64 gram arrow.

    If you use a 150 lbs bow, the velocity of a 64 gram arrow will drop to approximately 60.4 m/s.

    64 gram is the lightest 'livery' arrow when they are made of ash. In the medieval period they would use ash, as pointed out by Ascham. Any arrows lighter than 64 gram are arrows to "gall" horses and the enemy or kill unarmoured men.

    It's widely believed that these arrows with short square-heads were personal practice arrows the archers brought with them as part of their indenture (contract). It was require of an archer to bring 24-40 arrows when signing up for service. Most of the fighting was actually raiding and killing during a chevauchée, and these general-purpose arrows did the job. When battle was about to commence they were issued arrows by the Crown with arrowheads made to a specific pattern.
    1332 needle bodkins
    1346 needle bodkins and spear heads.
    1359 needle bodkins and spear heads, 10 % type 16 made of steel
    1362 needle bodkins and spear heads, 30 % type 16 made of steel
    1368 Triangular bodkins and type 16, all of them made of steel
    1405-12 Spear heads/plate cutters, triangular bodkins, type 16A, swallow out type 16 and small Tudor bodkins. Case-carburized spear heads/plate cutters and brazed on steel barbs on the type 16 and Tudor bodkins.

    You might wounder why they chose triangular heads and then went back to spear heads/plate cutters. Triangular heads were good enough to defeat wrought iron plate in 1368, but they were also lighter and therefor the kinetic energy when striking was not as good as with a spear head/plate cutter. The momentum is also significantly higher with a heavy arrow and the lozenge-shape will do better when shot into textile armour. A plate cutter or spear head will also penetrate deeper. A triangular bodkin requires less kinetic energy than a square head, actually less than 50 % if the sides are 5mm, but then in turn they'll buckle more easily if shot into quality plate. In 1415 they would use these as 'byker' arrows, or harassing arrows at long range against plate armoured enemies.

    Most of these issued arrows are from around 75 to 114 gram, depending on the length and size of the arrowhead. 20-25 % of these heavy arrows would have 8 to 9 inch swan or peacock fletchings to stabilize the arrows at short range.
    Arrows with needle bodkins are usually from 85 to 96 grams, depending on the length of the arrowhead. And they are almost always long if we take a look at the needle bodkins from the Museum of London.
    As a general rule:
    Needle bodkins from 85-96 gram
    Spear heads from 85-100 gram
    Plate cutters from 100-114 gram
    Triangular bodkins from 64-85 gram
    Type 16A from 75-85 gram
    Type 16 and 64-75 gram
    Sweep-out type 16 from 64-85 gram
    Type 16B and Tudor bodkin 50-64 gram

    Here are the results after testing with a 150 lbs bow from the book The Great Warbow. They used a doppler radar to measure the velocity.
    108 gram arrow, 52 m/s = 147 J
    95.6 gram arrow, 53 m/s = 134.69 J point blank, 43.3 m/s at 230 m = 89.9 J
    74.4 gram arrow, 57.8 m/s = 124.27 J point blank, 44.9 m/s at 258 m = 75 J
    57.8 gram arrow, 62.25 m/s = 111.98 J point blank, 48.3 m/s at 295 m = 67.4 J
    53.6 gram arrow, 64.3 m/s = 110.8 J point blank, 48.9 m/s at 320 m = 64.1 J

    If you use these numbers and plot them on a graph you can read off whatever arrow weigh you'd like. For instance, 64 gram will give you 60.4 m/s. 80 gram = 56.5 m/s, 85 gram = 55.4 m/s. 90 gram = 54.25 m/s. This will give you 116.74, 127.69, 130.43, 132.43 Joules, respectively.
    I don't know it you can see it, but the heavy arrow (95.6 gram) have 40 % more kinetic energy at max range in comparison to the lightest arrow. At point blank range the advantage is about 20 %. The 108 gram plate cutter have 32.5 % more kinetic energy, point blank.

    But take a look at the momentum also.
    108 gram = 5.616 N*s
    95.6 gram = 5.0668 N*s
    74.4 gram = 4.30032 N*s
    57.8 gram = 3.59805 N*s
    53.6 gram = 3.44648 N*s

    The light arrow will only have approximately 61.5 % of the heavy arrow's momentum. So almost 3/5.

    This will give a great advantage when inflicting blunt trauma to the target. Momentum is conserved, so either the arrow penetrates, or, the target moves accordingly, and with soft armour you are done.

    If the 108 gram arrow have 66 Joules left after plate penetration (for the sake of argument), the arrow still travels at 34.96 m/s. Therefor the momentum is 3.77568 N*s, and that is even more than the 57.8 gram arrow.

    You calculate it like this: Square root (66*2)/0.108 = 34.96 m/s

    If the 53.6 gram arrow penetrates plate with 80 Joules, there is only 30.8 Joules left, and the momentum is only 1.81704 N*s. However, If the 53.6 gram arrow had 66 joules left, the momentum would be 2.659632 N*s. That is a huge difference.

    For a quarter pound (114 gram) arrow to shine you need a 170 lbs bow. Charles II is reputed to have complained: 'No one is left to shoot a quarter-pound arrow!' Someone else, I don't remember who, said there was 2000 archers in England at their height to shoot quarter pound arrows. If they fielded 10 000 at any time during the Hundred Years War, then the rest could probably shoot 150 lbs bows, and bows in between. This also makes sense when we take a look at reproductions of the Mary Rose bows and their numbers. The 120 lbs bows were probably for the sailors or secondary bows to be used against unarmoured targets when rapid shooting was required. Further more, this is what you'll be able to handle if you practice from an early age, something many archers, such as Joe Gibbs and Simon Stanley have demonstrated. And they are in full command of their bows.

    Around the middle of the 15th century they developed a long plate cutter with a cross section like a + with two of the sides wider than the others. This will maintain the structural strength and at the same time increase the arrows ability to shear the plate (and textile armour). You will also get reduced weight, so you can either make the arrowhead longer for deeper penetration, or, better penetration at long range with a shorter version. You also get better results when you case-carburize the arrowhead because it's thinner. Some of the "Tudor" bodkins we have are grinded down arrowheads of this sort.
    With a 167 lbs bow you'll reach 58.82 m/s with a 85 gram arrow of this shape and 147 Joules. Simon Stanley demonstrated this.
    "Alea iacta est"

  3. #63

    Default Re: English Longbows w/ No Penetration?

    I agree with you, but some of the sources are dubious while some others have no point.

    Lets just take the first two you mentioned, David II of Scotland and Philip VI, took wounds, to the face, and lived to tell the tale...and you take this as evidence of the warbows overpower against armor?


    Holy hell, I would wear any helmet that allows me to survive arrow shots to the face lol.

    Also, your calculations are not that wrong, but you are perhaps unaware the Dr. Williams was not using armor shapes for his tests, but a flat metal sheath, which a lot of people argue skews the test in the arrows favor, as it is a different thing completely to fire at a flat and fixed sheath and a shaped armor part that has better structure and gives in to force a bit into the cloth beneath and the non-rigid human body when struck.


    But I do agree with your over point, high end warbows could indeed penetrate both mail and plate armor, it is just that at the same time I believe that armor worked a lot of times as well.

    For instance, I consider the source you provided;

    The arrow pierced the blazon of William Despencer, and through three folds of mail armour, and through three plies of acqueton, and into the body, so that he lay there dead of the blow.’
    Strickland & Hardy, The Great Warbow 2005 p. 268-9

    to be complete and utter bull .

    Three folds of historical mail would require 300+ J to penetrate even at point blank, this is obviously a romantic exaggeration, just like that source describing an arrow penetrating both sides of the armor and killing the horse beneath the rider, which is ridiculous and nonsensical.

    So yes, arrows could penetrate plate, but plate could also stop arrows.
    Last edited by Mamlaz; September 10, 2017 at 11:22 AM.

  4. #64
    Ichon's Avatar Praeses
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    Default Re: English Longbows w/ No Penetration?

    I am not sure who else besides Ascham is still convinced about Ash being the most prevalent for war arrows. http://warbowwales.com/warbow-arrows/4588842944

    As for long and low fletchings... relative to what? Minimize drag for the capabilities of the time but nothing close to what we have today. 64 grams is a heavy arrow, all I am pointing out about weight is 170lb draw bow is what would typically be used starting at that weight yet there is quite a bit of evidence that bows in the 120-140lb were the most typical with bows at 170lb and above relatively rare.

    When stating a premise like this it seems a bit better to use averages as much as possible. Most people who have read the work done in the past 20 years on English archery accept that low quality plate can be pierced by English longbows sometimes- how often in a typical battle and how the English fit longbows into their tactical battle plan during several of the famous battles (including those where English lost) is difficult to reconstruct. I've done a dozen posts just on twcenter since I started talking about stuff other than just the games explaining all the math and converting to joules etc.

    In the list of arrowhead weights you posted you can see most of the type 16's are not the heaviest arrows- plate cutter arrowheads typically weigh 23-27 grams by themselves. I do think English archers were specialists and had very specific uses for the arrows they had which combined with changing armors and manufacturing constraints makes it difficult to get a good picture of average type of arrows used without lots of experimental testing with period based reconstructions. The other thing is how English archers were typically used in battle- you are correct most of the fighting was done via raids and personally I don't believe any old archer was using all the types of arrows issued. More experienced and stronger archers would get better equipment and in a full scale battle be deployed to the front of a group of archers to make best use of their strength and skill as the distance narrowed and relatively shallow angles reduced the effectiveness of the archers standing behind.

    I mentioned the horizontal and vertical axes of an arrow strike against armor because so far as I've seen almost all tests are done vs flat iron plates of the correct quality which as has been pointed out many times doesn't really match characteristics of rounded plate even of munitions grade/low quality. Budget constraints make doing full scale tests of recreated period armour unfeasible but the few tests done in small numbers I've seen does indicate it makes a noticeable difference.

    Anyway- don't take this as denying arrows could penetrate some plate at times, it just doesn't ring true that even low quality plate was easily defeated by English or eastern bows. Establishing how easy/hard it was when talking about thousands of men and archers in the same battle is probably going to take another 20 years or more of expiramental research.

  5. #65

    Default Re: English Longbows w/ No Penetration?

    Mamlaz

    An arrow in the face does not necessarily kill you, but it surely reduces your ability to fight. Henry V was extremely lucky when an arrow struck him in the face. It entered at an angle next to his nose and penetrated to a depth of 6 inches (15 cm). Can you imagine the feeling? It probably struck one of the breaths.

    Mark Stretton have done some testing on globulous shapes on a dead pig and it doesn't matter much, he even penetrated plate at a 40 degree angle. Striking a globulous shape is like striking at an angle. Within that small 1mm*1mm when the arrow get purchase to full penetration, the angle turns to in between the x and y axis. There is no reason to test arrows against plate with a globulous shape other than as a random test. You do tests in isolation and combine them afterwards with math. If not you'd have to carry out several hundred thousand tests to get the whole picture. Alan Williams' test was a drop test, and the results he got are inferior to actual results with bows and arrows against the same type of plate, even with bigger arrowheads, such as lozenge-shaped plate cutters. It probably has to do with momentum and impedance matching. With bullets momentum doesn't make much difference, there kinetic energy is king, but with arrows it's an important part of what is going on. His test only gave us a general idea of what is needed in terms of kinetic energy.

    This is 2mm modern case-carburized mild steel with manganese, if my information is right. Manganese will increase the ductility of the steel. The fracture toughness is probably way past 260 kJ/m2. More likely around 300 kJ/m2.
    https://www.facebook.com/rasmus.d.ra...type=3&theater
    As you can see it doesn't matter muck for the arrow to get purchase when it's a spear head/plate cutter.

    If the mail was made of wrought iron and large rings, and the aketon was really thin and the arrow was a heavy needle bodkin shot form an elevated position, it might penetrate three layers. However, we shouldn't generalize from this of cause, but it might be true. However, 3 folds of good quality mail and padding would require a lot more kinetic energy than 150 Joules. Probably around 300 Joules.
    Take a look at this. Two layers of case-carburized mail. The mail is not the best quality, but the arrow didn't break the ring at the joint, as is usually the complaint, it shattered the whole ring and split it in two.
    https://www.facebook.com/rasmus.d.ra...type=3&theater
    "Alea iacta est"

  6. #66

    Default Re: English Longbows w/ No Penetration?

    Quote Originally Posted by Strategos Autokrator View Post
    Mamlaz

    An arrow in the face does not necessarily kill you, but it surely reduces your ability to fight. Henry V was extremely lucky when an arrow struck him in the face. It entered at an angle next to his nose and penetrated to a depth of 6 inches (15 cm). Can you imagine the feeling? It probably struck one of the breaths.
    Well, firstly, to my knowledge, Henry remained in combat after the arrow strike and secondly, to my knowledge it is generally accepted that he did not have a visor or his visor was up.

    But the point remains the same, they lived, even with arrows in their faces they lived.

    The argument is that armor still increases your chances by a lot even when penetrated, because not only is the penetration lower, but the energy dispersed by the plate section of the armor is immense and thus, the damage to the surrounding tissue the arrow goes through is lowered significantly as well.


    Quote Originally Posted by Strategos Autokrator View Post
    Mark Stretton have done some testing on globulous shapes on a dead pig and it doesn't matter much, he even penetrated plate at a 40 degree angle. Striking a globulous shape is like striking at an angle. Within that small 1mm*1mm when the arrow get purchase to full penetration, the angle turns to in between the x and y axis. There is no reason to test arrows against plate with a globulous shape other than as a random test. You do tests in isolation and combine them afterwards with math. If not you'd have to carry out several hundred thousand tests to get the whole picture. Alan Williams' test was a drop test, and the results he got are inferior to actual results with bows and arrows against the same type of plate, even with bigger arrowheads, such as lozenge-shaped plate cutters. It probably has to do with momentum and impedance matching. With bullets momentum doesn't make much difference, there kinetic energy is king, but with arrows it's an important part of what is going on. His test only gave us a general idea of what is needed in terms of kinetic energy.
    Firstly, Mark Stretton is an awesome bowman, but he is obviously a big longbow enthusiast and fanboy, the reality is that curved surfaces have much better structural integrity when struck and when penetrated as well as actually having a longer amount of material en route with the same angle compared to a flat surface, as pictured here;

    Spoiler Alert, click show to read: 



    So again, shooting at a fixed flat sheath is not the same as shooting at a cloth supported shaped armor part.


    Quote Originally Posted by Strategos Autokrator View Post
    This is 2mm modern case-carburized mild steel with manganese, if my information is right. Manganese will increase the ductility of the steel. The fracture toughness is probably way past 260 kJ/m2. More likely around 300 kJ/m2.
    https://www.facebook.com/rasmus.d.ra...type=3&theater
    As you can see it doesn't matter muck for the arrow to get purchase when it's a spear head/plate cutter.
    Firstly, the arrowhead is also modern steel.

    Secondly, that armor worked really well imo.

    The point is not that the arrow bounces off(even though that would obviously be the best scenario), but to minimize the arrows impact and damage, which that breastplate did.

    Quote Originally Posted by Strategos Autokrator View Post
    However, we shouldn't generalize from this of cause, but it might be true. However, 3 folds of good quality mail and padding would require a lot more kinetic energy than 150 Joules. Probably around 300 Joules.
    Take a look at this. Two layers of case-carburized mail. The mail is not the best quality, but the arrow didn't break the ring at the joint, as is usually the complaint, it shattered the whole ring and split it in two.
    https://www.facebook.com/rasmus.d.ra...type=3&theater

    That mail is obviously not the best quality, look at how thin the flat rings are, that is some Indian stuff bought on eBay.


    Quote Originally Posted by Strategos Autokrator View Post
    If the mail was made of wrought iron and large rings, and the aketon was really thin and the arrow was a heavy needle bodkin shot form an elevated position, it might penetrate three layers.
    Not a chance in hell.

    Your own example of Dr. Williams clearly stated how many J is required to penetrate a single coat of mail + gambeson, and the more important point you do not just add the value three times;

    because the arrowhead will be slowed down and blunted by the impact of the first layer and then the second layer as well before even reaching the third layer of mail!

    The same argument is made for full mail shirts worn under plate armor(which was very popular for quite a while everywhere), you cannot just add value, you have to consider the loss of velocity and blunting of the arrowhead on impact with the plate before it even starts to penetrate the mail beneath.

  7. #67
    Ichon's Avatar Praeses
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    Default Re: English Longbows w/ No Penetration?

    In addition to what Mamlaz noted about arrow that does successfully penetrate plate slowing very rapidly as the edges of the arrowhead scrape the edges of the hole in the plate additional layers all have their own properties and deflection. One of the main reason so many were wounded in the head other than having visors up was the front of a helmet is not only nearly the weakest area with good armour coverage (not a gap) but just about the most exposed part of a person when advancing vs arrows coming down from the top part of their flight arc.

    Heavier arrows do have more momentum but significantly less range as well usually require larger bow.

  8. #68

    Default Re: English Longbows w/ No Penetration?

    Mamlaz

    That picture is not representative to your point. The radius is 100 mm and the thickness 20 mm. The additional material you have to go through in comparison to a flat surface, will increase with thickness. Imagine the pipe with a thickness of 30 mm, and there wouldn't be any penetration at all. But the biggest problem here is the radius.

    The normal relation between radius and thickness on, say, a rerebrace would be a diameter of 140-150 mm and 1.5 mm thick armour. That's a radius of 75 mm to 1.5mm! At a 45 degree angle on a flat surface the arrow would have to penetrate 2.12 mm. If you have a big compass you could scale this rerebrace up 16 times (radius 1200 mm and thickness 24 mm) on a big piece of paper and measure the added thickness and see for yourself. At a 45 degree angle the thickness would be as close to 2.12*16 = 33.92 mm it gets. You wouldn't be able to measure the difference. On a breastplate you have a greater radius and even less effect.
    "Alea iacta est"

  9. #69

    Default Re: English Longbows w/ No Penetration?

    You are using the thickness analogy needlessly, just use the length difference depicted in the length of the line, which is obvious;


    Spoiler Alert, click show to read: 



    Also, as silly as the comparison sounds, you can also look at beam penetration comparison between a flat, curved and concaved surface;

    https://www.nde-ed.org/EducationReso.../Curvature.htm

    the image to the right visualizes what I am trying to say perfectly.

    I failed to find any text about structural effect, but that could perhaps do.

    Simply put, even if you remove the thickness argument completely, the flat surfaced sheath will still suffer a more pronounced collapse of structure compared to the curved surfaced armor shape and will thus, suffer easier penetration.

    That is my argument, I will see if I can find anything actually connected to projectile penetration to back this up and I will get back to you.

  10. #70

    Default Re: English Longbows w/ No Penetration?

    Alan Williams tested mild steel mail with a Vickers plate Hardness of around 235.
    He also tested a 15th century almost slag free slack-quenched low carbon-steel/wrought iron gusset with alternating bands of ferrite (iron) and bainite. About 60 % ferrite and 40 % Bainite. The ferrite had a VPH of 168 and the bainite a VPH of 235.

    The arrowhead was the same arrowhead he used against the plate. A short square-head bodkin, and not a needle bodkin.
    The padding underneath the mail was a jack with26 layers of quilted linen. That is a lot!

    First he tested the modern mild steel mail.
    At 80 Joules two links were broken. After this he increased the kinetic energy to 100 Joules. Now the jack was holed completely. With 120 Joules the mail was completely defeated with two links completely opened out and three others bent. There was a 5mm hole through the jack and a 35 mm hole in the plastilene behind. In other words, the socket prevented deeper penetration when it got stuck in the jack.

    When he had established 120 Joules to be enough kinetic energy, he tested the 15th century mail gusset with 120 Joules. The arrowhead completely defeated the mail and broke two rings.

    But here is the problem with the test. First, the arrowhead was not the best against this type of armour, a lozenge cross section would be better and a needle bodkin and type 16 the best. Second, he started at 120 Joules, and this armour was inferior to the modern mild steel. If he had tested the mail several times the way he did with the mild steel mail, by starting at a lower kinetic energy value and increase it gradually, he might have achieved the same with 100 Joules or even less.

    I don't know the diameter or thickness of the rings. That information is of major importance. Because this was a gusset the rings are probably not too big and at the same time thick enough to make a difference.

    26 layers of quilted linen is not thin armour, so there you have a problem if you use this as a comparison. About half the kinetic energy goes into defeating the jack. Thin rings of a greater diameter made of wrought iron with 3-4 % slag and thinner padding would not require 100-120 Joules. Far from it. Add a needle bodkin to this, and there you have it.
    "Alea iacta est"

  11. #71

    Default Re: English Longbows w/ No Penetration?

    Quote Originally Posted by Strategos Autokrator View Post
    Alan Williams tested mild steel mail with a Vickers plate Hardness of around 235.
    He also tested a 15th century almost slag free slack-quenched low carbon-steel/wrought iron gusset with alternating bands of ferrite (iron) and bainite. About 60 % ferrite and 40 % Bainite. The ferrite had a VPH of 168 and the bainite a VPH of 235.
    Yes, and he also used modern steel for the arrowheads as well, without giving any information(as usual with tests), something everyone seems to ignore.


    Quote Originally Posted by Strategos Autokrator View Post
    In other words, the socket prevented deeper penetration when it got stuck in the jack.
    What?

    What do you mean by this?


    Quote Originally Posted by Strategos Autokrator View Post
    But here is the problem with the test. First, the arrowhead was not the best against this type of armour, a lozenge cross section would be better and a needle bodkin and type 16 the best. Second, he started at 120 Joules, and this armour was inferior to the modern mild steel. If he had tested the mail several times the way he did with the mild steel mail, by starting at a lower kinetic energy value and increase it gradually, he might have achieved the same with 100 Joules or even less.
    You are correct that the arrowhead is not the best type for it.



    Quote Originally Posted by Strategos Autokrator View Post
    26 layers of quilted linen is not thin armour, so there you have a problem if you use this as a comparison. About half the kinetic energy goes into defeating the jack. Thin rings of a greater diameter made of wrought iron with 3-4 % slag and thinner padding would not require 100-120 Joules. Far from it. Add a needle bodkin to this, and there you have it.

    Actually, it is not clear which quilt he used.

    Further down Williams describes two different types of padding and is unclear which was used behind the mail. One was a jack made of 26 layers of linen, which he says was used in the testing(could be the separate one), but the other was only 16 layers of layered linen which he specifically says was made "to simulate that under armour".

    But the point remains.

    Let us go your route and say that 60-70 J is required to penetrate (good)mail without gambeson and then add +20 after each layer for arrowhead blunting and velocity loss.

    That still results in 240-270 J required to penetrate three layers of mail which is written in the source I declared folly.

    That is, without the gambeson.


    To that point, mail armor was basically always used with a shield, which really sideways the entire line of tying it with the plate armor vs longbow discussion.

  12. #72

    Default Re: English Longbows w/ No Penetration?

    This guy is pretty definitive, he has a whole range of great segments on medieval armor and weapons:
    https://youtu.be/q1WZLVZYBwQ
    https://youtu.be/HMvz-z1SPLQ
    https://youtu.be/X9fHmXxaXqQ
    Last edited by Point Blank; September 15, 2017 at 04:56 AM.

  13. #73

    Default Re: English Longbows w/ No Penetration?

    This looks interesting
    https://youtu.be/t1ZbrkVkm-8

  14. #74

    Default Re: English Longbows w/ No Penetration?

    Mamlaz

    That was exactly my point. If we take a look at your second picture, the arrow striking at a forty five degree angle against the flat plate, will strike the curved plate at probably sixty degree angle or there about. This will increase the kinetic energy required by 100 %, exactly. If it's at a sixty five degree angle it's 136.62 %. At a seventy degree angle it's 192.38 %. But this requires the plate to be of very poor quality and the arrowhead to be of very good quality. If not the armour will deflect the arrow. A warbow can not reach these numbers if it's a breastplate. Jones penetrated slightly at a sixty degree angle in his test on mild steel, but at a seventy degree angle the arrow ricocheted off the plate.

    If you want the arrow to strikes at a perpendicular angle to the rounded surface you need accuracy. Or, as the law of averages dictates, lots of arrows. However, it doesn't matter much if it's at a ten to twenty five degree angle.
    Here is a guide in percentages. Let's say a perpendicular strike requires 100 Joules. By using 100 you get the increase in percentages.

    0 degree angle = 100 Joules
    5 degree angle = 100.38 Joules
    10 degree angle = 101.54 Joules
    15 degree angle = 103.53 Joules
    20 degree angle = 106.42 Joules
    25 degree angle = 110.34 Joules
    30 degree angle = 115.47 Joules
    35 degree angle = 122.08 Joules
    40 degree angle = 130.54 Joules
    45 degree angle = 141.42 Joules
    50 degree angle = 155.57 Joules
    55 degree angle = 174.34 Joules
    60 degree angle = 200 Joules
    65 degree angle = 236.62 Joules
    70 degree angle = 292.38 Joules
    75 degree angle = 386.37 Joules
    80 degree angel = 575.88 Joules

    A curved plate have better structural strength. However, this is predominately something that effects blunt weapons. If we are talking about piercing points you will not see any significant effect. I have actually heard that a curved surface aids penetration because there is less kinetic energy wasted on bending the plate inwards. If you have any information to disprove my prediction I would be very interested.

    Apart from what I have mentioned, the reason a breastplate have a globulous shape is to lift it off the body to distribute blunt trauma away from the center.


    I meant the arrowhead was smaller than the diameter of the socket and arrow shaft at it's widest point. The socket and arrow shaft will not sher the textile armour (when the KE is low.) The textile armour will tuck in around the socket and stop deeper penetration.

    The Jack was most likely the textile armour he used underneath the mail he tested. It's clear from the list of results on page 943, Appendix 9. If you look at the results for the Jack versus arrowhead there's no number in Joules. It only says "see mail expts". He never tested the Jack on its own. Only in combination with mail. The 16 layered linen textile armour he called "padding" was only tested against a blade and lance. If you take a look at "padding" versus arrowhead there's only a line, no number. There is a possibility the 16 layers of linen was underneath the mail whereas the rest, 10 layers of quilted linen, was on top of the mail. This will give you 26 layers, but I doubt it.

    In other words, one time he wrote "Some modern (mild steel) mail, backed by a quilted jack, was tested" and another time he wrote "see mail expts" under arrowhead vs. jack. And one time he wrote "padding" (to simulate that under armour)". This last part might just as well represent the textile armour he tested the lance and blade against and it's simply a mistake on his part. Did he make 2 mistakes or 1? I'll say he tested the mail with the Jack underneath.

    I wouldn't worry too much about blunt arrowheads if we talk about needle bodkins. They pass through the rings and break them open. They do not penetrate plate. There is not much wear on the point, and textile armour will not blunt the point much. The difference between an arrowhead made of modern steel and one made of wrought iron will not be significant when shot at mail. Needle bodkins are made of iron for this reason.

    My scenario, the one you are arguing against, did not include good mail. There's no reason to continue this discussion. I can just keep on increasing the diameter and reduce the thickness of the rings in the mail and take away layers of linen from the 3 aketons, and an arrow will eventually penetrate. It's a complete waste of time.
    Last edited by Strategos Autokrator; September 17, 2017 at 05:17 PM.
    "Alea iacta est"

  15. #75

    Default Re: English Longbows w/ No Penetration?

    It does not necessarily matter how accurate the shooter, because the target is constantly moving around.

    Curved facings can also be seen in AFV turrets such as Russian tanks of the T-55 type onwards up to the T-90. They are a compromise between deflection and turret space.

    We have multiple historical samples, ie pieces of armor with holes in museums etc, of plate that was penetrated by firearms and far fewer that were holed by crossbow bolts; there are pretty much none caused by arrows.

    The evolution of armor, then as now, was largely driven by improved projectile performance. Arrows do not figure in this equation hardly at all, if at all.
    Last edited by Point Blank; October 04, 2017 at 03:32 AM.

  16. #76

    Default Re: English Longbows w/ No Penetration?

    Edited the above for clarity.

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