Draw weights

[Bede]

I think we are in danger of confusing the issue here by covering too wide a historical perspective. The Dhanuveda is very ancient and refers to early Indian archers using bamboo bows. The text that was translated on this site was corrupt by which I mean that it had many later additions. When the original parts were written, armour was unknown in India. It does stress the importance of archers, the title means the bow scripture. While women warriors are mentioned Indian texts, they are usually bodyguards protecting the inner part of the palace and not field troops.

Tutankhamen bows were probably the personal possessions of the Pharaoh and likely build to his needs at the various times in his life he used them. He was not a very robust individual and probably could not draw a very heavy bow. It is unlikely he ever intended to lead his troops into battle.

I agree with Jack that a wide range of bow weights would have been used and they would have been suited to the individual. In the Strategikon of the Emperor Maurice, he writes that the strongest archers should be up the front and the beginners should be down the back with weak bows. Stephen pointed out to me that this seems counterproductive, but I suppose they were learning on the job and only shot arrows at high elevations of the heads of the troops in front of them.

Adam is right too, the English archers were not a militia, but were professional soldiers and the records of their pay still survive. Later Persian and Indian texts show an acute awareness of the positioning of expert archers in the battle line. The Ottomans were renown in Europe for the professionalism of their troops.

I have to check an account I have, but I remember the report of exceptionally strong bows being used in target completions by Manchu bannermen. The Kangxi emperor's letters about hunting also indicate the use of very strong bows.

However, everyone from the Emperor Maurice down recommends using a bow that you control, not one that is so strong to it controls you.

[jack farrell]

No reason for apologies at all, we are just friends having a discussion. Adam, thankyou for letting me make my point about sampling.

I only mentioned the Dhanurveda as a source describing built up bows which might be considered composite for the discussion. I did mean women archers in battle, possibly Hindus.

Tut was not a robust guy but all pharoes were groomed for battle, this can be demonstrated redundantly. Whether they led, followed or read about it later is all open to debate. The decoration on his bow might be a good reason to exclude them from any analysis. But as McLeod points out, even his puniest bow falls within the paramaters of bows used in Africa for hunting.

I also believe that it can be shown that initiates were taken by English into battle.

My point now is another possible source for statistical error. Namely, the exact construction technique of a composite bow, which can probably be only approximated at this late date.

While making angular composites(will show soon) I was completely surprised that a very thin slice of Ibex horn could easily be rolled into a complex knot. Honestly, I have only cut up one waterbuffalo horn and its texture was plastic, even thin slices were springy and rigid. Ibex-goat horn- had the same feel as longhorn cattle horn. My thinking is that it does not have nearly the compression resistance of waterbuffalo.

Indeed Adam, my bow lacked the draw weight guessed at, maybe because of design reasons, or general lack of reflex, but maybe it is because of the difference in compressive strength of Ibex as compared to WB.

You demonstrated to me convincingly that maple is superior to Ash, wild ungulate sinews are preferrable to domestic. Therefore consideration must be made to horn species. Horn is not horn. And if I am not mistaken, WB is not the preferred species for Turk bows.

This is just an observation; when the tests come it I want credit for mentioning it first. Ha. -j-

[Adam Karpowicz]

Water buff was the preferred species, the second was longhorn cattle from a certain area in Turkey. I am surprised you found cattle horn to be so flexible, this was not my experience.

You make a good point about the ibex, this should be taken into account for other replicas. On the other hand, if horn is thin, it should not matter that much. This kind of changes can be calculated in to make sure the replicas are not too far off.

Adam

[raygun]

Hi guys, long time no see.

About the draw weight of the example bows you had the pleasure to examine, will the age of the bow had anything to do with such heavy draw weight?

I mean as the glue and wood age, would they have become harder, less elastic and more brittle,which contributes to the immense draw weight? 120 lbs is alot of weight. Its like trying to pull a woman up using one hand. How many shots can a good archer possibly do?

Its frightening to think about power it generates....

Just some thoughts.

cheers

[Adam Karpowicz]

Old bows were measured, then the dimensions compared with new replicas of known draw weight.

Adam

[Bede]

From what I have heard of compression test of horn, there is not a lot of variability in compressive strength. They are all made of keratin. However, this is not the same as flexibility. Even Payne-Gallwey was impressed with the flexibility of the buffalo horn when removed from the bow it was part of (

The component parts of a Turkish bow, consisting of a thin strip of horn, one of wood and another of sinew (fig. 3, p. 6), are so pliable when separated that they can almost be coiled round the fingers, though if the same pieces are glued together they form a bow of of unrivalled strength and elasticity.

Page 15. A Treatise on Turkish and other Oriental Bows of Mediaeval and Later Times).

The change of structure of the Egyptian army during the new Kingdom meant that in the start of the period the Pharaohs took a major role in military operations. However, Tutankhamen's father Akhenaton was noticeably uninterested in military pursuits. The one reproduction angular bow that I have shot, based on one of the Tutankhamen bows, looked thin and weak, but shot extremely well. It could project a long heavy arrow as well as any bow of the same weight. I think that these bows are underestimated when you just look at pictures. At short draws they are under-stressed, but they really perform at the draws Egyptian arrows suggest. For a detailed view of how the New Kingdom army worked, I can recommend War in Ancient Egypt by Anthony J. Spengler, Blackwell Publishing, 2005.

[Adam Karpowicz]

I understand the flexibility in this context means stiffness (modulus). I have doubts about Payne-Gallwey's tests - I suspect he separated the materials in water, possibly hot water (this is why he had those rubbery fragments for sinew). Moisture-laden horn is indeed very bendy. It also applies to green horn as I have determined when using goat horn, fresh from the animal, which later stiffened considerably. Perhaps your bow, Jack, will gain a bit of weight as it dries, after all.

I could not resist checking this business with horn and made some calculations. If the modulus of horn is halfed in a flight bow, to make the horn much more flexible (not likely, even for ibex), the draw weight drops only by a few percent. It is because the horn is only a part of the total thickness of limbs. So, I doubt if it really matters which horn is used for the composites, unless the horn is very thick, although it would be better to test.

Adam

[Bede]

The weakness of Payne-Gallwey is not just what state the horn was in when he was describing it, but also the fact we have no idea of what thickness it was to begin with. Adam has suggested before that Payne-Gallwey may have used hot water to disassemble a bow. This would make the flexibility of the horn greater.

One of my friends did some compression testing on cylindrical horn sample pieces. He could not get a large range of types of horn and I don't think that he did bending tests. It is a worthwhile idea to run a series of tests on the main types of horn for bow making. Aside from different species, it would be useful to compare different parts of the horn, horn from animals of different ages and also horn that had been treated differently such as boiling, heating etc.

Edward McEwen made angular composite bows up to 80-90 pounds at 28 inches. He said they performed extremely well at longer draw lengths.

It would be interesting if Jack tested the performance of his bow at six monthly intervals. If Adam is right, there might be a measurable improvement in performance.

I haven't seen any publications another area that might be interesting is in the microscopic cross sections of various horns to see if they differ in structure.

[jack farrell]

Very interesting discussion Gents. When the weather warms up a bit I will post on my latest bow. It was shot alot last fall, is now approaching one year since its last sinewing.

What would one think of as green horn? Mine was from a mature animal which died of natural causes several years before being cut. -j-

[Adam Karpowicz]

Horn dries slowly, I think green would mean about 6 months. Your horn is fully dried after several years.

Adam

[Tuukka Kumpulainen]

As you all know, the debate over the original English warbow pulls has been going on at least since the 1920's, with the common argument against the high poundage claims being mostly the very low number of modern archers capable of shooting even a 80# bow accurately. Therefore, the low pull theorists say, the drawing abilities of the Medieval archers on average cannot have been very high, even though there had been exceptional archers like Simon Stanley today capable of the famous 120 to 170# pulls.

Nowadays, however, there's a "second generation" of modern English warbow shooters emerging. Their experiences may shed light on the potential ancient composite bow pulls, too. More and more (mostly English) archers are drawing and shooting longbows in the 100 - 130# range, and most of them are self-admittedly not exceptional in physique. What's astounding to me, is the fact that many of them haven't been shooting any bow for more than a few years, and initially struggled with 50# weapons like any average male. Yet, with a couple of years of dedicated warbow practise, quite different from the modern target style, these 160-pound guys are pulling weights close to their own mass.

Just thinking of the days when bows were the long range weapon, with an actual need for extremely strong archers, the peer pressure in the ranks of those young men with the sole goal of pulling at least the same as the next guy, and I feel certain the 120# average pulls emerging from the bow data on both Europe and Asia are very realistic no matter how far from common archery practise today.

[Bede]

Tuukka,
You have a valid point. If you look back in archery literature, you see a gradual change in the nineteenth century from believing that people used to have very strong bows to a belief that what contemporary archers were shooting was probably what ancient archers used.

I think that was a first step in the rational analysis of historical archery. You must start from evidence. Up until the Mary Rose bows and skeletons were excavated, there was not any unequivocal evidence for the use of very heavy bows. Composite bows were not a good example because there were so many ways of altering their draw weights that earlier authors were uncertain.

More historical literature is now available and it is better understood because of a developing understanding of the context. For instance, Manchu documents in China refer to one occasion where an archer competed in a target competition for heavy bows with the equivalent of a 200 pound bow. Adam Karpowicz has demonstrated Turkish bows perform well at higher poundages by building detailed replicas and testing them in an objective manner with a shooting machine which eliminates the archer as a variable. There have always been difficulties in cultures that have a long tradition of archery literature because weights and measures changed over time and in other places. It was hard to identify which ratl (Middle Eastern weight) or tan (Chinese weight) was meant in a given document.

All this doesn't mean we should all be shooting 120 pound bows or that our ancestors did. There would have been a spread of archers in armies between the strong shooters, the accurate shooters and those who just made up the numbers. A strong, accurate shooter would be an asset to any army.

[Nick]

I think an important point to consider here is the exact type of shooting required for military archery - and how it would influence bow weights used. Speaking from my own experience of English war-bow 'replica' shooting, I find that my English 'war-bow' of just over 100 pounds was OK for 'roving marks' style shooting - generally at longer ranges. However, I do not find it easy to use much more than about 60 pounds for closer range target type shooting and field archery (in composite bow or longbow), unless I can find alot of time for practice. I find the heavier bow too clumsy and difficult for this kind of shooting. Military archers would be required mainly to excel in long-range shooting - so heavier bows would be preferable. A great deal of individual accuracy was not generally required as archers would mainly be shooting into the mass of the enemy. It is also intresting to note that when target shooting with the longbow ('prick shooting') became more popular in the 16th century, it was not approved of by supporters of military archery. It was considered that it encouraged men to use lighter bows. The truth is that the pursuit of fine accuracy does favour more moderate bow weights and that too much draw weight is counter-productive. There has been a general downward slide in bow weights in target archery for a long time now - that is still continuing.

[Adam Karpowicz]

While I completely agree with Tuukka, I do not believe target archery (as Nick is saying) has to be done with light weight bows. the key factor is practice and the drawn weights are relative to the archers' strength. If an archer draws 100lb, his target bow may indeed be best at 60lb, but for a 150lb archer, this wll raise to 100lb. In any case, it is an open question if the ancients actually used lighter bows for target practice at all - perhaps they had only one "heavy" bow to use, given the expense in manufacture.

I believe it was a well known American archer (I forget the name) who stated that any healthy male should be capable to work up to a 100lb. I was too a 50lb archer for several years, then began using an exerciser to practice off-season. The progress is very fast at first, then it slows down somewhat. I can now draw over a 100lb, but my heaviest target bow is 85lb. I have no doubt at all I can still go up, if I wanted, although more practice is necessary. A 50lb bow feels like a pleasant toy, allows me to hold at full draw forever, and I understand why this tendency to go down with the weight.

Instead of endless discussions as to what were the draw weigths, how about actually making an effort to try? I guarantee after 6 months of exercise the draw weight will go up by 20lb, and after another year up by 40lb. Obviously, the ancients had plenty of time to practice and the tougher individuals would join the army.

Adam

[M Hardman]

In which way is it best to weight train for archery? Do I have to splash out on some equipment or can I just practise pulling a heavyier bow than I usually shoot.

I ask because I am relatively skinny but I can pull a much heavyier bow than Lads who beat me in other strength sports,

Mike