the question says it all

the only thing i can think of is that sitting down, with your feet not touching the ground, isnt cconducive to be able to get as much push out of your body to draw a stronger bow as easily, however that is pure speculation on my part.

Where are you getting information that horsebows are lighter than footman bows? Who's horsebow (Asian, middle east, western Europe?) and what time period? And what are you classifying as a "foot bow"?

Just curious, because from what little research I've read, testing of extant renaissance turkish composite bows from museums showed that they are much heavier on average than what is believed the Mary Rose longbow weights were on average. Of course, Turkish composites can often be short enough to be used on horse, but may have been used on foot as well.

It's also arguably difficult to determine what some of the extant composite bows were intended for (military vs. long range hunting or sport shooting). And summarily in the comparison to English longbows to later middle-eastern bows, for some of us it's like comparing apples to oranges. Or samurai swords to broad swords, if you will.

-Terry

[quote="Terry Thompson"]Where are you getting information that horsebows are lighter than footman bows? Who's horsebow (Asian, middle east, western Europe?) and what time period? And what are you classifying as a "foot bow"?

Just curious, because from what little research I've read, testing of extant renaissance turkish composite bows from museums showed that they are much heavier on average than what is believed the Mary Rose longbow weights were on average. Of course, Turkish composites can often be short enough to be used on horse, but may have been used on foot as well.

It's also arguably difficult to determine what some of the extant composite bows were intended for (military vs. long range hunting or sport shooting). And summarily in the comparison to English longbows to later middle-eastern bows, for some of us it's like comparing apples to oranges. Or samurai swords to broad swords, if you will.

it;s a commonly asserted idea that bowa used y cavalry are of lower poundage

one example i know of being that chinese military exams listed a higher limit for foot archery officers than cavalry officers.

i dont recall the exact ficgures but the maximum for foot archery bows was i believe 50lb's higher than those intended for cavalry

although the mention of the turkish bows of higher draw weight than the mary rose bows is interesating

im open to being wrong as always

Anecdotal evidence of course, but I have tried archery both on foot and mounted. And even with a lot of practice, there is simply too much going on when you have to keep the horse under some kind of control, while travelling quite fast and at the same time draw and aim..I can fully appreciate that the last few pounds of draw get lost along the way.

The most obvious thing is that while on foot, you brace your feet to the ground, on horse you brace against the horse. And even if you practice a lot together, the chance is always that any uneven distribution of force through your legs will signal the horse to veer to one side. When your hands are occupied with the bow, all communication to the horse has to go through your seat and legs, so you have to allow for some movement there.

What about comparative arrow weight? From what I inderstand, the weight of a flight arrow is vastly less that that used by the English longbow. Wouldint this also be a factor connected to chosen draw weight for the bows?

Turkish military flight arrows were about 20g, and heavy short-range arrows about 40g, to deliver more energy due to higher efficiency with the heavier arrow. Or use about 30g for an all-purpose arrow. Indian arrows are about the same weight. Turkish non-military flight arrows could be as light as 10g.

Compare with, say, 80g for a war arrow for longbows. (80g is a middle-of-the-road estimate. Very likely, 100g was not unusual. The classic heavy figure from literature is 1/4 pound, which would be about 90-110g depending on the pound.)

This doesn't depend on the draw weight, except that very light arrows might not be possible since they need to be strong enough to survive being shot. It depends on the mass of the limbs of the bow. If the arrow is too light compared to the limbs, the moving limbs get most of the energy stored in the bow. If the arrow is too heavy, it moves too slowly (but has a lot of energy). At a suitable compromise weight of arrow, its speed is a reasonable fraction of the maximum attainable speed (of a very, very light arrow) and its energy is a reasonable fraction of the maximum attainable energy (of a very, very heavy arrow).

Some graphs showing this in http://myArmoury.com/talk/viewtopic.php?p=179617#179617 (and the maths 2 posts earlier), or in http://arxiv.org/abs/1101.1677

A longbow has heavier limbs than a typical Asian-style composite bow as used in Eastern Europe, the Ottoman Empire, India, Korea, and Ming-and-earlier China. So, to obtain reasonable efficiency, the arrow should be heavier.

Not only are the limbs shaped differently with different weight distributions, there is also a difference in force-draw curve. The longbows build up a lot of their total draw weight in the last couple of inches, while the typical siyah tipped composite has a force draw curve that will result in more even arrow acceleration.

The longbow's force draw curve makes sure that a) there is a lot of power put upon the arrow at once and b) the amount of energy that is available for pushing the arrow rapidly decreases.
Both cases require a heavier arrow: if it is too light, it would a) shatter and b) leave the string before the full energy potential is transferred to the it. The composite bows typically release their power more gradually.

As Terry Thompson said: "it's like comparing apples to oranges. Or samurai swords to broad swords, if you will."

so

how come the chinese military exams which both use composites have that large discrepancy of draw power between cavalry and infantry catagories?

Like Bjorn already said.

Also, an archer on foot can easily turn so as to be in the best position to shoot in the desired direction. On horseback, you can shoot most easily straight to your left (assuming right handed). To shoot forward or backward of that direction, you won't have the ideal posture. Not as easy to use a bow at the limits of what you can draw if you aren't in the ideal position.

If you have a bow and want to goof around a bit, you can try the difference for yourself. Just prop up a beam or short log perpendicular to the target where you normally shoot. Straddle it and give it a go! You will sure appreciate the difference. Just make sure your feet do not touch the ground, that is cheating ;)

That is how many horsearchers start out anyway, so you are in good company :)

Their 150-160lb estimate is at the high end of estimates. They might be right, but they're also high draw-weight partisans. The low estimates give about 115lb as typical for the Mary Rose bows. Alas, the draw weight depends on the cube of the thickness of the limb, so small errors in measuring the thickness translate into large errors in draw weight (whether measured using a replica, or obtained via mathematical modelling), and changes in thickness due to their long immersion matter a lot. I don't know whether the low estimates assumed the same draw length (i.e., Strickland and Hardy's 30"), or whether they assumed a short draw length. (30" is the average Mary Rose arrow length, so 30" would not be achievable with a large fraction of the arrows.)

It's also claimed in The Great Warbow that 100g and up arrows demand 143lb and up bows (pg 18). This is a half-truth. As they continue, such bows will deliver such arrows out to 220m and beyond. This kind of range isn't necessary for the arrows to be useful or effective. Japanese and Qing archers used heavier arrows from weaker bows (with the caveat that they had more energy from the same draw weight due to convex force-draw curves (Qing) longer draw length (both Qing and Japanese)), and considered them effective. Use such heavy arrows at your typical battle range of 10-20m, and lighter arrows for long range when you need to.

There's no written documents on this (yet), but when I was last at an English Warbow meeting, conversations with a few top Warbow bowyers resulted in me being told that the most up to date average estimate is 150lbs.

This is based on close examination of the smallest bows which both Jaro Petrina and Dave Pim (two leading bowyers in this field) believe are around 110lbs, and analysis of replicas made by both Steve Stratton and Alistair Aston of the largest MR bow (MR 81 1607) which were made using European yew with identical ring count and density and would be close to 196lbs if they were made the same length. Both replicas were made a good 4" or so longer for safety, and a bow increases in weight with every inch it gets shorter.

That gives a low end estimate of 110lbs, a top end estimate of 196lbs and an average of 153lbs.

Bearing in mind this estimate isn't based on only caliper measurements but actual bows built to those measurements using the same quality yew from the same geographical location.

If anybody on here is a member of the English Warbow Society, you can see all the replica bows on the society forum.

With Mark Stretton having proved that 200lbs is achievable with 5 years dedicated training, and Joe Gibbs shooting 170lbs on a regular basis with the ability to shoot much much heavier (in fact I think he's shot an elm bow made by Daniel Taralund of 202lbs a while ago, but would need to clarify that) it seems that 150lbs is perfectly sensible as an average weight for soldiers trained to use them.

There are guys all over the world today shooting well over 150lbs without too much trouble - Glennan on this forum for instance, and a fantastic young bowyer and archer called Ian Sturgess who's just mid twenties and very slight in stature is shooting 160lbs at least - so a recruitment of dedicated archers brought up shooting heavy bows would easily be looking at that weight plus much more.

I should add as well that although draw weight is relative to the thickness, with wood you cant use that as the only method of estimating. You can make two dimensionally identical yew bows from two different trees and see well over 60lbs difference in final weight, depending on the health of the tree, the growing conditions, the density and so on.

Just recently for example I finished an English yew bow that I roughed out to dimensions I was certain would give me 50lbs, based on previous bows of English yew I had made. When tillered and finished it was 105lbs. It's smaller than one of my American yew 70lb bows, and the same size as a few 50-60lb English yew bows, yet has double their weight.

Using yew that is close to the original artefacts and making replicas is really the only way to tell. If you made an exact replica of an average MR bow from low density English yew or American yew, it would come out hugely different to one made of high altitude Alpine Yew.

The problem with Mary Rose replicas is that an error of 1mm in the thickness translates to about 10% error in draw weight. I don't know how accurately the amount of expansion due to waterlogging can be estimated - it's probably about 10%, but if it isn't known to better than a few %, that's a potential 1mm uncertainty in thickness. We have the uncertainty in original thickness, errors in measurement, and errors in reproducing the intended thickness in a replica. These add up, and it wouldn't be hard to get something 25% higher or lower in draw weight, just from thickness alone.

I'd have more confidence in a 150lb estimate of the typical or average draw weight if:
(a) all parties gave very similar estimates (they don't), or
(b) the whole procedure was validated. AFAIK, this hasn't been done, and I don't know if it is really possible. The recipe is simple: start with a bow of known draw weight, and leave it underwater, anoxic, and wait. Then retrieve, measure and replicate/model. Compare draw weight determined thus with the original. The "wait" in that recipe is a problem. (If this has been done, I'm interested in details.)

That said, they might be right. 150lb isn't impossibly high. But it is high. If naval archers are a special case (compared to archers in the army), then it looks like a good number (compared to perhaps 120-130lb for regular archers). Nobody else appears to have gone to such high draw weights (i.e., 150lb) for average/typical/standard bows (though individuals certainly shot such draw weights and higher), so 150lb deserves to be treated with some caution.

On one hand, one could say that since longbows deliver less energy per pound of draw weight than reflex-recurve composites and Japanese bows, high draw weights are needed to get the same performance; therefore the English used 150lb instead of 110-130lb for their typical longbow. On the other hand, you can't have too much energy when you're trying to put arrows through armour, so those who used 110-130lb as their typical draw weights would have preferred to use 150lb as typical, if feasible. Why would it be feasible for the English and not for others? Maybe the English case is special. What kind of draw weights did other late Medieval military longbow users use?

I don't think 150lbs is high at all. When you see how many guys today are shooting that weight, you realise it's pretty achievable with a bit of hard work. And that's just guys doing it for fun on the weekends, not life and death or a career. Pretty much any healthy man can learn to shoot 100lb bows in about a year, so it seems highly unlikely that 130lbs would be an average weight for fully trained archers who spend a lifetime shooting. If you can shoot 196lbs, why settle for 130lbs, for example?

I also think that naval archers would be shooting LOWER weights than soldiers on foot. There's no plate armour on ships, nor are there any large distances to cover. Both of these elements are present on the ground during the high middle ages, so it stands to reason that the MR bows may be lighter than those used previously.

Part of me believes a substantial amount of damage has been done by self proclaimed experts like Bickerstaffe, who publishes books and gives talks on the theory that the MR bows are much lighter than people think, but the theories are always based on since-disproved fallacies such as string types etc.

The truth is, we've got guys like Joe shooting 170lb bows (that are smaller than the MR bows) comfortably, and as I mentioned he's not doing it for warfare. He's doing it for enjoyment. I think 150lbs is a very likely average, with plenty able to shoot far, far heavier bows.

I do however agree with the idea of making a dimensionally perfect replica and seeing what similar submerging would do to it. That would be fascinating.

Infantry draw weights of 150+lbs appear in various Chinese-region military exams and texts. Some these exams mandated 30 or more arrows, so to pass such an exam an archer could theoretically handle the required bow - or a slightly lighter one - in the field. According to Stephen Selby's Chinese Archery, a Tang-era exam involved shooting over 30 arrows from a 168lb (76kg) bow. Similarly, a Song-era exam required a 161lb (73kg) bow for infantry. And a 1201 Ruzhen Jin exam specified 148lb (67kg) infantry bows. I'm sure many more such records exist. In the late Ming era, as you've noted previously, T'ien-Kung K'ai-Wu wrote that strong archers draw 159lbs (72kg) [120 catties] - and the context of the passage suggests field usage. So we only need assume most of the archers on the Mary Rose were strong archers to make Strickland and Hardy's average of 150-160lb consistent with many Chinese-region sources.

As far as they modelling goes, Hardy's faction does have considerable evidence from both models and replicas on their side. The beginning of The Great Warbow goes into this in detail (from that position, of course).

The performance of 150lb English yew warbows according to The Great Warbow stands broadly consistent with period accounts. If anything, period accounts overall indicate superior performance. Even with heavy arrows, a 150lb Mary Rose replica isn't likely to penetrate the worst sort of mass-produced 16th-century munitions plate under battlefield conditions according to The Knight and the Blast Furnace. 2mm of wrought iron takes 88 J to just penetrate with an ideal (perpendicular) hit. Curvature makes it 105+ J in most cases, and then you have padding too. Etc.

Really, English archers need 150lbs as the standard. 150lbs with the standard lightish poplar arrows from the Mary Rose are bad enough. If I recall correctly one replica poplar arrow shot from a 150lb replica bow only managed 100 J initial energy. And longbows of inferior wood post downright abysmal numbers compared with quality composite bows.

Will S wrote:

I also think that naval archers would be shooting LOWER weights than soldiers on foot. There's no plate armour on ships, nor are there any large distances to cover. Both of these elements are present on the ground during the high middle ages, so it stands to reason that the MR bows may be lighter than those used previously.

I tend to agree, but plate armor definitely played a role in naval combat, albeit less so by 1545. But if I recall correctly they still found remains of breastplates and such on the Mary Rose itself.