Page 1 of 1

Chu-ko-nu and composit bows

Posted: Mon Sep 15, 2008 3:47 am
by ellisv75
I don't clame to be an expert but I have read some and seen severeal different shows documenting Ghengis Khans horse cav. The consensus being that the composit recurves have greater range and penitraiting power then the english long bow. Thats easy enough for foot troops .. give them long bows but for cav there is no long bow option. Any thoughts ?

What about the Chu-ko-nu ... seems a cross bow with shorter range reduced fire power and shot from the hip insted of aimed would perform very differently, not to mention from a few things i have read the ROF is 10 in 15 seconds while the arbelast is 2 in a minet.

Posted: Mon Sep 15, 2008 7:34 am
by philqw78
This subject has been covered a lot in this forum. Depends who you want to believe.

Posted: Mon Sep 15, 2008 1:54 pm
by caliban66
Well, in mongol bow had been so good, they would have been able to conquer almost the whole world, isn´t it? No, wait. They did! :wink:
I think that a game must provide enjoyable rules, and must be able to allow balanced matches. In FoG, you can see a "balanced" game of Classic Greek hoplite army against mongols, e.g. But during the classic period, most of hoplite armies rarely had more than 1200 hoplites (about five bases in FoG standards) while the mongol horde was much bigger. How can you represent the effect of 20.000 horse archers against 1200 hoplites?

Posted: Mon Sep 15, 2008 2:57 pm
by hammy
In game terms there isn't a lot of difference between a superior mounted archer and an average longbowman in terms of shooting ability. The Mogols would be better against targets with less armour and worse against armoured infantry and all heavily armoured troops. While there were definitely instances of knights being shot up badly by Mongol archery it was normally in conjunction with evading/avoiding the knightly charge.

FWIW I would be very surprised if the power of a mounted composite bow was anything like that of a longbow. Power is a combination of draw weight and draw lenght, the longbow had both a high draw weight and a long draw length, a mounted composite bow may have the weight but I don't think it had anything like the draw lenght of the longbow.

Posted: Mon Sep 15, 2008 3:02 pm
by nikgaukroger
Longbows and composite bows of comparable draw weights are known.

However, one of the big differences between the two is, I understand, that in general longbows shot heavier arrows.

Having played with shooty horsemen and longbowmen in games I'm personally happy that their effects are pretty much correct - and both fall short of various myths attributed to them :D

Posted: Mon Sep 15, 2008 4:20 pm
by Redpossum
The advantage of the longbow that's hard to model is the greater impact at the target end because of greater projectile weight.

After all, Ke=MV^2

Also, all other things being equal, a heavier projectile has a higher ballistic coefficient (crudely put, is slowed down less by the drag of the air), which would result in higher retained velocity at the target end.

So, given that a "clothyard shaft" definitely has more "M" and probably more "V" as well, I think the longbow as modelled in FoG is just right.

Posted: Mon Sep 15, 2008 7:24 pm
by ethan
possum wrote:The advantage of the longbow that's hard to model is the greater impact at the target end because of greater projectile weight.

After all, Ke=MV^2

Also, all other things being equal, a heavier projectile has a higher ballistic coefficient (crudely put, is slowed down less by the drag of the air), which would result in higher retained velocity at the target end.

So, given that a "clothyard shaft" definitely has more "M" and probably more "V" as well, I think the longbow as modelled in FoG is just right.
I believe one issue with longbows this overlooks is that the arrows themselves (being relatively long) vibrate quite a bit which dissipates a lot of the energy.

Certainly, when I was at the Turkish Army Museum in Istanbul (one of the best museums I have ever been to for ancients gamers) the Turks claimed some pretty impressive archery feats/ranges/penetration/accuracy/etc (from horseback and on foot)...Now I am sure the Turks are happy to toot their own horn, but no more so than longbow enthusiasts I suspect.

The Mehtar band (Turkish army official band) certainly puts one in the mood ton conquer things...

Posted: Mon Sep 15, 2008 7:25 pm
by OldenTired
caliban66 wrote:Well, in mongol bow had been so good, they would have been able to conquer almost the whole world, isn´t it? No, wait. They did! :wink:
and surprise surprise, a mongol horsey-shooty army is extremely difficult to beat with most other FoG armies.

Posted: Thu Sep 18, 2008 11:57 pm
by lawrenceg
hammy wrote:In game terms there isn't a lot of difference between a superior mounted archer and an average longbowman in terms of shooting ability. The Mogols would be better against targets with less armour and worse against armoured infantry and all heavily armoured troops. While there were definitely instances of knights being shot up badly by Mongol archery it was normally in conjunction with evading/avoiding the knightly charge.

FWIW I would be very surprised if the power of a mounted composite bow was anything like that of a longbow. Power is a combination of draw weight and draw lenght, the longbow had both a high draw weight and a long draw length, a mounted composite bow may have the weight but I don't think it had anything like the draw lenght of the longbow.
Not quite so simple.

The "power" i.e. the energy imparted to the arrow depends on the draw weight at all points throughout the draw (the "draw curve") and on the efficiency of the bow/arrow system, i.e. the amount of energy that was in the bow that is transmitted into the arrow. Composite (recurved) bows are more efficient and have a more favourable draw curve compared to simple bows such as the longbow.

The net result is that a composite bow can be designed to shoot the same arrow and with the same energy as a longbow and the composite bow would be shorter, so handier to use on horseback.

The question is, in practice did they design their bows to match "longbow" performance, or were they optimised for another kind of arrow, or shorter so as to be more useable from horseback?

I read somewhere that the Mongols used a second, longer bow for use on foot, so the mounted bow was probably less powerful. I also suspect it was not their (nor any shooty cavalry's) practice to carry large amounts of armour-piercing ammunition. Different nations with other fighting styles or opponents may have had differently optimised bows, perhaps for long range shooting with lightweight arrows or rapid shooting at short range not requiring so much power.

Posted: Fri Sep 19, 2008 3:46 pm
by spike
lawrenceg wrote:
hammy wrote:In game terms there isn't a lot of difference between a superior mounted archer and an average longbowman in terms of shooting ability. The Mogols would be better against targets with less armour and worse against armoured infantry and all heavily armoured troops. While there were definitely instances of knights being shot up badly by Mongol archery it was normally in conjunction with evading/avoiding the knightly charge.

FWIW I would be very surprised if the power of a mounted composite bow was anything like that of a longbow. Power is a combination of draw weight and draw lenght, the longbow had both a high draw weight and a long draw length, a mounted composite bow may have the weight but I don't think it had anything like the draw lenght of the longbow.
Not quite so simple.

The "power" i.e. the energy imparted to the arrow depends on the draw weight at all points throughout the draw (the "draw curve") and on the efficiency of the bow/arrow system, i.e. the amount of energy that was in the bow that is transmitted into the arrow. Composite (recurved) bows are more efficient and have a more favourable draw curve compared to simple bows such as the longbow.

The net result is that a composite bow can be designed to shoot the same arrow and with the same energy as a longbow and the composite bow would be shorter, so handier to use on horseback.

The question is, in practice did they design their bows to match "longbow" performance, or were they optimised for another kind of arrow, or shorter so as to be more useable from horseback?

I read somewhere that the Mongols used a second, longer bow for use on foot, so the mounted bow was probably less powerful. I also suspect it was not their (nor any shooty cavalry's) practice to carry large amounts of armour-piercing ammunition. Different nations with other fighting styles or opponents may have had differently optimised bows, perhaps for long range shooting with lightweight arrows or rapid shooting at short range not requiring so much power.

You are right in that the power is delivered more consistently from a re-curve (eastern) , than the selfbow (longbow) design, this leads to smoother and more consistent shooting. It however the materials in an eastern bow more susceptible to changing weather and atmospheric conditions.

However the further a selfbow is drawn, the more power per inch of arrow length, where the recurve is closer to being linear. lastly the power difference between the 2 designs comes down to the limb length, which means that the angle at the knocking point of the arrow is less on a longbow, than on a recurve bow. Therefore the arrow can be drawn further, as the fingers / thumb ring impinge less on the arrow.

There are plenty of 150lb draw wt bows in the Mary Rose, where there are no recurve Hunic style approaching that power, some of the Japanese kit may, I'm not that well up on far eastern stuff.

spike

Posted: Fri Sep 19, 2008 5:54 pm
by nikgaukroger
spike wrote:
However the further a selfbow is drawn, the more power per inch of arrow length, where the recurve is closer to being linear. lastly the power difference between the 2 designs comes down to the limb length, which means that the angle at the knocking point of the arrow is less on a longbow, than on a recurve bow. Therefore the arrow can be drawn further, as the fingers / thumb ring impinge less on the arrow.
There are actually quite a lot of illustrations of Turkish style composite bows being draw just as far as English longbows are illustrated being drawn (which is close to the right arm pit). I believe the thumb ring means there is very little contact with the bow string so the angle it creates is not too much of an issue. Also if you look at Chinese illustrations of Turkic and Mongol bows they are actually quite long - although not as long as a longbow 8)

Posted: Fri Sep 19, 2008 8:00 pm
by spike
nikgaukroger wrote:
spike wrote:
However the further a selfbow is drawn, the more power per inch of arrow length, where the recurve is closer to being linear. lastly the power difference between the 2 designs comes down to the limb length, which means that the angle at the knocking point of the arrow is less on a longbow, than on a recurve bow. Therefore the arrow can be drawn further, as the fingers / thumb ring impinge less on the arrow.
There are actually quite a lot of illustrations of Turkish style composite bows being draw just as far as English longbows are illustrated being drawn (which is close to the right arm pit). I believe the thumb ring means there is very little contact with the bow string so the angle it creates is not too much of an issue. Also if you look at Chinese illustrations of Turkic and Mongol bows they are actually quite long - although not as long as a longbow 8)
Nik
Most of the Eastern European/ Western Asian arrows in the "simon archery collection" at Manchester museum are less than 36" and most are about 32". The ones on the Mary Rose are at least 36", and some Japanese arrows in the museum are considerably longer (40"+).
Yes the bows are quite large when unstrung, but have an pronounced re-curve and a high bracing height when strung (some even have a bridge piece to stop the string from slapping the limbs on release.

The thumb ring is not something i have used, but i have seen one in use, and this would be an issue which would cause inaccuracy if the bow were overdrawn. Its the same problem that compound shooters have with their mechanical release if they overdraw.

Spike

Posted: Sat Sep 20, 2008 12:18 am
by philqw78
If you are a player that thinks eastern bows are better do what the lists allow and upgrade your shooters to superior. Better bow and better confidence in said bow. I'm sure the odds of a hit then become almost comparable to longbow against heavily armoured troops and better than comparable to their normal target than longbow is. And your troops perform better overall giving an effect equal to a far better bow.

but its late on friday