At the battle of Visby the bolts ripped through armour and there are Medieval reports about that. Thanks for finding out the draw length(must have missed it somehow).
Are you comparing a longbow shooting a 100g arrow to a crossbow with a 50g bolt?
I'm not really convinced they mastered the crossbow effectively because the bolt must match the weapon. If there were trials with a succession of different projectile weights for bows and crossbows we might get closer to the answer.
I totally agree with you that the presented combination is less effective in transferring kinetic energy compared to a longbow. But I have grave doubts that from this very limited trial any general information can be derived.

Ben,

Have you seen the Springald and Great Crossbow book that the RA puts out? It has a very clear set up for crossbows and their inmpact and initial energy in joules which seem much, much higher than those you are listing.

There are any number of issues with determining crosbow power. One key one is if the crossbow was even used for war or hunting as many of the hunting treatises clearly indicate they were not necesarily the same.


RPM

Ben,

Nope Jean Liebel based his figures off prototypes they created and then tested. The larger artillery was the ones they had to be a bit more theoretical as they could not build full sized models of them for whatever reason.

In the end for the 13th century on we have a pretty good idea on bolt length at least because they were, like the longbow arrow, somewhat standardized. From Philip Augustus on the state is ordering bolts of at least 12 inches. Since anything much more than the bolt head past the prod would destroy the functioning of the crossbow I think we can assume that it is at least 10.5 or 11 inches from prod to the nut. From what I can tell they are still requiring the same sized bolts for what seem to be steel prods in the 15th which is odd as it seems to be often seen that the steel prods lowered thus length. At least from the written record this seems an interesting set up. We also have notes for 24 inch bolts listed for crossbows (Liebel states they are for crossbows of the two foot variety) and 3/4 and 4/5 a yard for the larger giant crossbows or springalds.

As well in written sources such as the report before the venetian government in the late 15th the longbows are compared to crossbows both being able to penetrate armour, something that it seems they had assumed was only possible by the crossbow before. That said it may be that they are looking at the best of the best or it being possible over all of them doing this as I am sure some crossbows could not do this. As well it seems crossbows in medieval sources are more likely to penetrate than their warbow counterpart as they seem to show up more often doing so.

Of course I think generally speaking crossbows are very misunderstood. Just like bows we have different bolts in use for crossbows. So we might have arrows that are intended for long distance shooting or close up penetration. The same is true for crossbows. We have at least 3-4 heads that seem to have been in use for crossbows and I am betting it is not the only differences. I figure just like arrows bolts weight is a major factor.

As well more so than bows there is a great variety in power of crossbows. The use of cranks, windlasses, mechanisms for spanning clearly were developed due to major draw weights. If the effect was of no or limited use to older models they would never have been developed. We have a large amount of types of prods which affect the possible power generated. So i am sure some crossbows were less powerful than warbows that said I am sure that there were a large number if military crossbows in use that were stated by contemporaries as being more powerful. My guess is most crossbows on the lower end used for war were in the same ballpark as warbows

You mentioned 240 lb draw for a bow earlier. What is the source on this? I have looked at a fair number of Asian bows and that was the first I have seen close to that high. Was it to show how strong someone was like in the Odyssey, kind of a you think you are a man try this bow sort of account? Seems like such a bow would be rather useless for practical use on a large scale as most people even practices would have a hard time on such a bow.

Timo,


Didn't the Qing draw upon mostly Manchu leadership and officers? Do you think this might have been what reinvigorated the push to upgrade the military after over a hundred years of decay under the Ming. Seems like the decline of firearms was simply tied into a number if issues the dynasty was suffering at the time as some decline is going on in agriculture from Yuan and especially the Song dynasties. Sad how the brilliant dynasty came to an end on such a low note but declines usually come before the end. From my limited readings on the Qing seems cavalry was a major part of their military, why didn't they ever adopt methods to combine the two artillery and cavalry?

RPM

Payne-Gallwey is an excellent source and he brings up an issue we have not yet discussed, arrow gliders. They were something in between the bow and the crossbow because they enabled to shoot shorter projectiles with the bow and hence less aerodynamic resistance. I remember that arrowgliders and crossbows were both used on the warships of the high-late Medieval Eastern Mediterranean by Muslims and the Byzantines. Another source is the Muslim conquest in Central Asia where they were employed by mounted archers to fight other mounted archers.

There's an issue I tried to look up, but have so far not been succesful. The angular speed of the bow/prod, except for compound bows, slows down the more relaxed they become. The projectile becomes faster, while being propelled forward and the speed difference between the propelling spring and the projectile diminishes and in turn the acceleration. These Turkish weapons were recurve bows with very long levers, greatly increasing the speed this relaxing spring could transfer . In turn outstanding feats with ultra-light projectiles were feasible.

Ben,

It really is a great book. The info is also in the Appdx. on how the models were created and employed.

The PG bolt likely was too light for such a beast of a crossbow to get an idea of the max joules possible for it. At least by Liebel's calculations. That said I figure that is along the lines of what I was talking about earlier regarding a wide number of bolts for various uses.

His info for the one foot crossbow is 80 grams bolt and the prod to nut is some 31.5 cm/about 1 foot, 17cm/about 7 inches from rest to nut. 350lb draw

He did no actual tests against armour but makes many conclusions.

Here is his impact joules given

Springalds- 1782

Windlass Crossbow- 627

2 foot crossbow-331

crossbow-126

That picture you linked does not look medieval to me. In fact it has a very modern artist sig at the bottom left. Once again artwork is a dangerous standard. For me text is much more useful, especially inventories from the king. Besides that you likely have much more showing simply the head past the prod. For example a brief look of some 30 crossbows in the Mac Bible showed all but one only having the head past the prod. All the crossbows in the milimete treatise of 1326 show the same thing, only the heads past the prod. While there are clearly examples of the opposite I would hesitate to assume it is accurate by this occurrence. To me it is a problem of basic physics. If you have any more than a few inches hanging past the prod it becomes less efficient to impossible, the bolt would simply fall earthward once discharged. I'd figure once you get in the 2-3 inch range this will take place progressively going from declining efficiency to completely impractical. I
still figure the 1-1.5 inches seems rather correct as what looks to be going on if the shaft is past the prod at all.

I have some pictures one of my students brought to class last Friday of an armoury in Germany from a trip she took some 10 years ago when she was a young teenager. The picture shows several walls full of crossbow bolts (there were some very military style crossbows as well present). The card stated it was 14-16th century war bolts resigned from service but never disposed of. It also said there were some 26,000 bolts in this bunch. They could not remember where they had been specifically but wondered if anyone had ever heard of such a collection. Ring any bells? I do not really read German but a touch and was very interested if the states were available for this collection.

RPM

Don't have really much to add, but 620 J with crossbow :

Quote:

Here is his impact joules given Springalds- 1782 Windlass Crossbow- 627 2 foot crossbow-331 crossbow-126

must be some mistake.

It would require speeding rather monstrous bolt weighing 150 g (I'm not sure if there even were beasties like that) to well over 90 m/s.....

Unless I've read something wrong in your post.

Cheers.

In this case, the windlass crossbow isn't a personal weapon but a device for defending or assaulting fortified positions. Here is an example of one in action.

Bartok,

No it is right just Liebel has his own terms he likes to use. It is not just any crossbow spanned by a windlass.
Ben is right, Liebel's windlass crossbows in his work refer to giant/gran crossbows. There were not personal weapons unless you were able to heft around 150-200 pounds and aim it....

That said it seems the 2 foot crossbows were sort of personal ones. Seems they were intended more for siege work both for and against. We see them fairly often in inventories of the 13th to 16th centuries.

After the raid of October 1338 on Southampton the town gets a few score sent from Edward III, along all sorts of military gear including a royal keeper and garrison to ensure the town does not fail again...

Regardless the great crossbows and springalds had as much joules of energy as early artillery which is why they hang on well into the 15th and in places the 16th.

RPM

That is upon impact not their initial energy. I believe that they are at impacts of 100-120 meters but yesterday misplaced my Great crossbow book.

As far as artillery you have few resources at hand that give specific joules of energy. Of course the great crossbows and Springalds is a good one to start with, though he tends to focus on certain large urban areas in select regions which puts his dating slightly off from what I have seen. For example he claims great crossbows died out around 1450 15th but it is fairly easy to find them until 1500 and after in use.

I'd also look into Bert Hall's Renaissance Warfare and the appendices of Alan Williams Knight and the Blast Furnace. Apart from that cannot think of much. You have to be careful regarding firearms of any size and testing because they rely on faulty information as few to no one uses proper powder and the amounts used is for the most part 100% guess work. Nothing is wrong with doing such testing but making medieval conclusions based on them is almost assuredly not correct. I got to watch some powder made off a 15th century recipe burn and it was visibly different to the modern black powder in how it burns and such.

RPM