"Don't really know what that proves. Just something to do on an afternoon." I think that a lot more KZfaq videos should start or end with that statement...

lmfao "No answers have come out of this". You are WIDLY entertaining man. I've watched about 25 of your videos so far and your work and demeanor are brilliant. Also I wouldn't discount your analysis here. That energy value is about the most useful objective metric one could come up with.

Many people tend to underestimate bows & crossbows. These things are definitely not toys.

I always thought medieval crossbows were far more powerful than modern ones. The speed of that modern crossbow and the energy was amazing . You have restored my faith here.

0:39 Bloody hell what have you done to that poor thing

That scale as seen better days my friend

what i learned from this video, if somebodies pointing something sharp and springy at you, BE SOMEWHERE ELSE

That last bit where you see the shots from the perspective of the target - might be just a nice addition for you, but for me it really brought home just how terrifying it is to be shot at by this things. Long enough to hear it coming, but short enough you've got essentially no chance of getting out the way in time. Thanks for adding it in!

I kinda hate the fact that a relatively cheap, modern, mass-produced Chinese crossbow is twice as effective as a beautifully hand-crafted medieval replica. But it's to be expected. We don't use graphite and fiberglass just to save money on wood and horn. Still, the mass produced one may win the speed contest but it will never beat the windlass in a coolness or beauty contest.

Projectile design is the most important factor when it comes to terminal ballistics, not MxV2. If you compare the crossbows' performance on paper, the 860 has 101J of energy but the comp has 129J, so you could say the compound is the better performer. However, the 860's bolt was stopped completely; therefore the entirety of it's 101J potential was released into the target. The comp's arrow passed through the target. If we assume the arrow was still flying at say, 47mps (to keep the sums simple) after it left the block, then the arrow still has 70J of energy remaining, meaning it dissipated 70J into the target - 31J less than the 860.

"All right you bow geeks, here it is" that statement made me smile.

i would repeat the test but swap the projectiles. Use the modern bolts and arrows on the medieval weapons and the modern weapons use the medieval bolts and arrows then compare the results with this test. This should show if the ammo is a major factor.

Tod I am an archer of some 4 years and a level 1 accredited coach and I find your videos amazing thanks for your time and efforts.

That electronic balance looks sophisticated

That's a slow compound bow at just 212fps. Looks like an early 90s bow? Maybe its a combo of factors, but something more modern would be interesting to see in a test. There was a huge increase in efficiency from 1995 to 2005. Today 310fps+ on a 60lb / 28" draw is easy to come by.

I really enjoy your comments, showing the energies and your comment about the thicker shaft of the long bow arrow having more DRAG. Too many times people do not take that into account. Great video

To truly compare them you should have the material and tip of the 4 bolts/arrows made out of the same material. The Longbow arrow is wood, much more resistant to move through the gel. I think the results would be different if the material was the same.

It would be interesting to see the same lineup pitted against gambeson, mail, lammelar and plate. But great stuff. I really like the math videos with chronos and numbers, they help put the difference between the weapons in context.

One thing to remember - tissue damage isn't just depth of penetration, it's also size of wound cavity. And in that, the old-school crossbow obliterated the rest.

The type of projectile is a huge part of wounding. trade a razor headed hunting point on that compound arrow and you have a whole different critter. the US pistol toters have finally figured this out. Projectile technology has gotten so good that 9mm is functionally equvilant to .40 and .45 as far as terminal ballistics, despite having less momentum.

The penetration figures as it relates to cross sectional area of the projectile is something that is often seen in firearms ballistics as well. Aside from bullet construction and velocity (as it more specifically relates to projectile deformity/expansion), the diameter of the projectile is another factor that determines penetration, or perhaps an inverse way of describing the same phenomenon, energy transfer to the target. I stumbled across your videos this afternoon and I'm enjoying them. Thanks for them!

This is what the history channel could be, but chooses not to. If someone told me in 2005 that content quality of media made by regular people would surpass that of TV networks I would have called them crazy. I love this channel. Outstanding work.

The numbers make perfect sense. Velocity = penetration. Your windlass crossbow has a lot of momentum due to the weight of the bolt, but that weight also makes it slow, leading to less penetration.

Back of the envelope calculations for energy transfer efficiency: Energy of Projectile/(Draw weight*Draw length*1/2) gives: Longbow~25% Windlass Cross bow~45% Compound Crossbow~65%

Loved this video, so cool to see these weapons in action and also their analysis (physics below!!) As for why the composite crossbow did went through more than the higher draw crossbow (reference to video at 8:50), here's the opinion of a first-year physics major university student: Let's look at the two crossbow bolt's speeds and momenta respectively. While the heavy draw crossbow bolt had around 1.5 times the momentum of the composite crossbow bolt, the composite crossbow bolt travelled almost twice as fast. If the same force was applied to the bolts in order to stop them (which is most likely a reasonably inaccurate assumption given the changing surface area of the bolts as they travel through the ballistics gel) then we can use the derivative form of the momentum principle to estimate that the change in momentum for the heavy draw crossbow bolt would take 1.5 times as long as the composite crossbow bolt. Let's say that the heavy draw crossbow bolt decelerated constantly in this time. It would travel at an average speed of half its initial speed (based on the final speed being 0 and the average being the initial plus the final, all divided by 2) until it came to a stop 1.5*x seconds later. If the other bolt was stopped a similar way it would be travelling at around the full speed of the heavy draw crossbow bolt on average (starting at twice the speed of it) for the total 1.0*x seconds until it stopped. By this simple math we can see that the second bolt would travel at twice the speed of the first for two thirds of the time, leading to a larger net distance. And this is why the composite crossbow bolt traveled the furthest through the ballistics gel. A similar example of this would be if a rhinoceros and a ping pong ball had the same momentum initially. They are both were stopped with the same force. The ping pong ball would have a much smaller mass and a much larger speed. The constant deceleration would apply to both making them stop after the same amount of time. The ping pong ball, however, started at a much higher speed and therefore would travel further before being stopped.

Thank you for an engaging video. Two points: firstly you mention hunting and hunting with crossbows is illegal here in the UK; second, it was very obvious that the windlass crossbow had a very short draw length so v=u+at applies and a longer draw length would have made a large difference. Please keep making videos. You are a master of your craft and the nuggets you drop are pure gold.

So with ballistics, speed is the biggest factor in penetration. So a heavier bullet, while will impact with greater force, speed penetrates much better. I would assume the same holds true, the heavier bolt creates greater impact force while the faster, lighter modern crossbow bolt penetrates better with speed. Think velocity vs. Lbs per square foot. (American here)

I've been shooting since I was six... and I have to say, your videos have taught me a lot, even if it's all in good fun.

It actually makes perfect sense, the momentum means stopping power, energy means distance to travel (grad neglected) and penetration (energy conversion)

Refreshing to hear someone say that they they don't know something instead of bullshitting. Enjoy his vids.

If you watched to the end (11:12 onwards) , does anyone notice now, during the one walk per day in March 2020 (quarantine in UK), just how loud the birdsong is now that the cars have gone? Also, the silence when you go out into the garden or yard at night. It's like going back in time.

Great video! I hunt with bows and crossbows quite a bit, and arrow/bolt penetration is something I definitely pay attention to. Velocity and mass play a major role, but so do a couple of other factors When choosing an arrow for extreme penetration on big game I want it to be (1) heavy (>400 grains) with weight distribution forward of center (more accurate), (2) I want it to have a small diameter, preferably thinner than the broadhead (less friction behind the head), and (3) I typically want a two-blade broadhead to decrease friction. Bolt diameter and the dullness of the point are two of the major reasons for the lack of penetration with the medieval crossbow, although there would be other factors.

My takeaways - Anything delivering near 2 joules will kill quite well. The windlass bow would knock you back from your feet like a lead slug, and the modern compound bow goes right through as a modern bullet would.

Penetration is a based mostly on velocity. Weight in the .5mv^2 calculation is a linear factor. Velocity though is squared before it is added into the energy calculation. This means that energy scales faster with velocity than with mass. You can find very similar parallels in bullets. A fast 9mm bullet will penetrate further than a slow .45 bullet even though the weight in grains of a .45 are higher. This is also the basis of current first generation railguns. Naval vessels (battleships) in WW2 could fire projectiles up to 1200kg in weight. The destructive power of current railgun technology rivals that of WW2 shells while only having a weight in the range of 10-15kg.

It's good data points and comparison. I build leverage artillery. I have one torsion machine, a giant in swinger Ballista. It's pretty new and we're still testing, but it's shooting 680 gram bolts and 450 gram bolts at 200+feet per second.

momentum is not what we usually use to calculate penetration potential. Generally kinetic energy is used. Momentum is just the tendency of the moving object to continue moving, kinetic energy is the measure of the moving object's ability to do work. Momentum can be interesting but go look at stats on bullets for hunting and the like and you'll see it's all about kinetic energy.

I wish I could have Tod teach me everything about life. Great video, man, as always!

Those modern bows just look so.. tacky.

These results make perfect sense in the context of physics. Penetration depth of non-deforming projectiles in a soft fluid-like medium is best predicted by the projectile's momentum per unit frontal area and momentum per unit lateral area. Even though the 860 lbf windlass crossbow produced by far the greatest momentum on impact, remember that its half-inch bolt has quadruple the frontal area of the other arrows and at least the same amount of lateral area if not more than the longer and skinnier arrows. I wouldn't want to be hit by any of these arrows; however, I think the 860 lbf crossbow would deal the most damage because it delivered the most energy inside the target and it punched a larger hole than the other arrows.

Many people who commented here obviously don’t hunt, so they have no idea about the significance of having the shortest noise-to-reaction elapsed time, and they have not seen how projectile velocity will help you in hitting moving targets with the shortest required lead. And there isn’t much mystery about momentum vs penetration, a ramming speed shopping cart filled with gold bricks might have larger momentum but it will not penetrate a non-AR steel plate better than a supersonic M855 5.56 tiny 62 grains projectile.

At the end of the day, this test shows the lethal effects of archery when the respective weapons are wielded by highly proficient archers. It must have been absolutely terrifying to have received repetitive mass volleys of these projectiles on the field of battle.

In firearms we often talk about sectional density. It is often more important to an ethical kill than any other number generally associated with ballistic. It has to do with how the bullet will behave in the animal. I’m not sure how it translates exactly to arrows but say if you had a stiff arrow it would probably penetrate deeper than one that flexed upon impact. Similarly if you had a think blunt arrow it would make quite a mess of thing and transfer a lot of energy but create a shallower wound compered to a thin pointy arrow that might go right trough but not leave much damage behind. Speed and weight are important but how the arrow behaves and dumps energy once it hits is what will determine how devastating a wound is. That’s why your numbers don’t translate. It’s about terminal ballistics not external ballistics. One doesn’t predict the other unless of course you use the same projectile in all four bows. A 308 won’t go as far or as fast as a 6.5 creedmore but it will take a bear much better. Sectional density. Cool video. It clearly illustrates the most misunderstood part of ballistics. It be interesting to compare those wound tracks and see which might be more appropriate for hunting deer as opposed to a hog. I bet that medieval cross bow would go right through a hog skull while the compound bow probably just bounce off.

I don't want to be hit by any of those, but it always shocks me just how slow those massive bows and crossbows seem to chuck their arrows/bolts.

You can do a similar test with sandbags between bows and firearms and the arrows will perform better simply because of the significantly smaller sectional density. Penetration is more heavily impacted by an object’s sectional density (or lack thereof) than pure kinetic energy. Objects with a small sectional density and 1/2 the speed of something the size of a thumb will penetrate further, depending on the medium. To put a point on it, sectional density and velocity are the keys to penetration rather than weight and momentum.

At 28 in draw the yew bow should do around 180 fps. Least that was my experience when I was building bows in the 90s. Good content and great video, thanks.

I suspect the 860 lbs crossbow didn't penetrate deeply because it's heavier but that does also mean more force was put into the target. You don't actually want your projectile to go completely through the target, instead, you want it to stop just before leaving and sub-optimally just after so the arrow head is out but the shaft is still in.

It proves that bows are fun!

The compoound bow you were using is a PSE Nova. Very good bow. I had one a few years ago.

The straight on flight of the longbow arrow at the end is in line with the archers paradox. Neat!

Medieval bows are perfectly effective hunting weapons. I would imagine that an order of magnitude more deer, hogs, and other game have been harvested using those medieval weapons than by using modern bows. The modern bows are more efficient due to better tech now, including better materials for construction and the whole notion of compound bows, but if you know what you're doing and can reasonably ensure a clean and ethical kill, the medieval ones are perfectly capable. Me, I just use a rifle. I don't know how to shoot a bow properly, and couldn't be reasonably certain of an ethical kill even with a modern bow. But I can with a rifle, so that's what I use. And I want to try hunting hogs with a spear.

Good video. When I first joined his lordship's retinue I was equipped with a Flemmish self loading longbow. Later we were told these new fangled bullpup automatic crossbows would injure far more dastardly Frenchmen. I know that his lordship's armourer spoke true, yet still today, given the choice I'd take back my self loading longbow. It gave the archer absolute confidence . When you hit the Frenchee he WOULD drop. It isn't all about numbers.

Might be worth plotting energy as a function of maximum frontal area of the shaft, so thin shafts have a bigger energy per area. Alternatively, have them all shoot the same arrow (probably the longbow one)

Great video. The compound bow number was interesting. It must be an older bow. PSE the maker of the bow used in this video actually has a bow that is capable of 370fps and is the current record holder.

I figure it's like the difference between a rapier vs a mace, or a modern hunting rifle vs an elephant gun. The modern crossbow has a smaller diameter projectile, is reletively smooth, and is going much faster because it's so light and easy to accelerate, so it's gonna wanna go straight through, rather than transferring that energy to the target. Meanwhile the big old medieval bolt is thicker, has the big broad head and wooden fletchings, and is way heavier, and stops in the target. If you watch back the footage, the medieval crossbow makes the gel block actually lift off the chair a bit, while the other bows just make it giggle a little. So I think what this test has trouble expressing is stopping power. If you are trying to shoot a deer with a thick hide from far away, you are gonna want that compound bow. But if you want to shoot someone who is charging towards you to attack you, you are gonna want that medieval crossbow. I bet if you tested those two crossbows against a hardened steel breastplate, the compound bow would bounce off, while the medieval one would leave a nice dent.

You should use a meat target for this. It would be super interesting to see the result.

I’d be interested to see how a lighter bolt in the 860 would perform.

As mr. Stephens said in another comment, please take into consideration the draw length.

It's worth remembering that in the day these old weapons were used, wounds that are now treatable would have been fatal. That big lump of a bolt dragging the fletchings through would have perforated organs and broken bones, and probably ended up buried inside you.

Transference of energy is also at play. The Medieval X-Bow dumped 100% of its energy in to the block, while the modern X-bow over penetrated and energy was lost. Don't get me wrong, I wouldn't want to get hit with either, but I think, against armor, the medieval bolt can act as a percussive weapon as well as a penetrating weapon.

Although the modern crossbow penetrated deeper than the windlass that doesn't necessarily mean it has less of an ability to penetrate. I think a more accurate view of penetration is "if" it can penetrate, not how far. The higher momentum of the windlass will allow it to penetrate armor more than the modern crossbow (which was its purpose). The modern crossbow was designed for hunting game and to hit "soft" (unarmored) targets.

First video of Tod's I've see with him wearing that moustache. And boy, is that a moustache

The configuration of the arrows counts too. If you equip the compound bow arrows with a 12 grain, 4 blade broad head you'll find that at a 70lbs. draw with a 60% let-off it'll perform better than the crossbow at that distance. The advantage of a modern crossbow is the range you get which is why certain states in the US reserve that, only, for hunters who have disabilities.

I'd like to see how the crossbows fire each others Bolt/Arrow for comparison. Particularly how the compound would fling that massive bolt into a block of gel.

At a given velocity, double the weight doubles the energy. At a given weight , double the velocity quadruples the energy.

Oh how I wished for thus kind of videos. Salute you, Todd! :)

Shoots various killing capacity weapons at house. But he does have that folding chair as a backstop...

Excellent video as always; your 'unscientific' experimenting is nevertheless more enlightening than practically all the 'well-researched' information I've found online. Overall, the results weren't far off from what I was expecting, although I did expect the bows to have ~30J more than they actually did. I will say I think the test is more accurate than you think, as my experience with modern bows and xbows matches what you saw here. My 175lb compound crossbow will absolutely drill through targets (excepting my burlap sack stuffed with clothes), and the bows my family and friends have used generally penetrate much less, on average roughly the distance you experienced. Now we just need to throw some gambeson in front of that gel and have another go at it. I suspect the slim arrows would gain an advantage over the fat bolt in that case. Maybe 1) Modern Xbow 2) Modern compound 3) Longbow (barely) 4) Windlass Now that I'm thinking more, I would think that the windlass would excel versus unarmored opponents, the longbows more against gambesons, and the windlass would again be preferable against heavily armored knights (slight stun/denting).

Penetration has a lot to do with the energy per square area on the impact site. Your Windlass has a fat bolt so it is slowed down a lot on impact. The compound crossbow had the lightest and slimmest bolt, so the deepest penetration. If they could all shoot the same projectile, the results would be more like what you would expect; the strongest bow would have the most penetration.

Velocity, hardened/tough tip, and cross sectional density/narrower diameter are the "Biggies" for *penetration* Momentum is the biggie for transferring energy that gives what's refereed to as "knockdown", not making enemies fly or silly stuff, no! but like a shotgun slug's ability to dump a HUGE amount of energy in a big area that wrecks hell on the poor recipient, enormous wound cavities, and often results in them being rendered "hors de combat" (be they 2 or 4 legged)

I like your approach and your commitment. In big game hunting it is proven that Momentum is much more important than Energy. That is why big game hunting rifles shoot a heavy bullet at a lower speed. The old British elephant and buffalo hunting rifles have proven themselves--, 404, 416 Rigby, 505 Gibbs , H&H 500 and 600 Nitro Expresses. The American Win Magnums are just too fast, the bullet runs just through with minimum damage. I plead ignorance with bows and crossbows. What is the best optimum weapon for hunting? What is the best sport crossbow?

For penetration of arrows, you can't beat a really sharp small broadhead. For cavity damage and bloodloss, a sharp and wide broadhead. To compare the bows, either use the same weight arrows for all tests, or tune the weight to get the same speed from all the arrows. Historically they used heavier arrows because they wanted maximum lethal range and weight carries more energy downrange. They were aiming at armies of thousands of soldiers at ranges over 600 feet, accuracy didn't matter much, but maximum range did. There is a sweet spot of arrow weight to maximize range and penetration.

this SEEMS to prove that speed is of the essence. the heaviest bolt shot with the highest draw weight didn't impact with the most energy, the crossbow with the lightest bolt and less then a quarter of the draw weight did.

I imagine the sectional density of the heavy bolt would allow more power at range

bottom line, archery/crossbows these are emotional sports, you do it because it makes you smile

The medieval crossbow had more energy, but the modern crossbow overpenetrated. What does that tell us? That the big 13mm medieval bolt transferred more of its energy into the ballistic gel than the smaller, probably sharper modern bolt. Once a projectile reaches the point of overpenetration (coming completely out the back), kinetic energy transfer is over - it carries any remaining energy with it (in this case, into the wooden wall). To summarize, while the medieval crossbow didn't hit with 4-5 times the force of the modern one, it did hit harder, transferring all its energy into the gel. No energy was wasted in overpenetration. It might be interesting to make a slow motion video of these various projectiles hitting the gel - especially if the gel were mounted movably, so that you could compare the impact energies.

When an arrow passes all the way through the enemy it is not transferring all of its energy to the target. The enemy gets a narrow puncture wound. If the fatter mediaeval crossbow bolt stays embedded in the target, it has transferred all its energy and also left a ragged hole that will be more disabling or lethal.

The heavier arrows would have more terminal velocity coming down out of the sky, as in the case of an arrow volley during a medieval battle.

I think it proves that Mass and Velocity are inextricably linked. I'm no ballistics expert, but the numbers seem to show that as you lower Mass and increase Velocity (enough) you can get similar Momentum(?) to the opposite condition of increasing Mass and lowering Velocity. As evidenced by the numbers Tod got for the 860# crossbow and the 95# Longbow. (87g, 158fps & 4.20 vs. 43g, 139fps & 1.82)

Ballistics gel works well for bullets, but its stickiness makes it cling to the shaft of an arrow, slowing it down dramatically.

Proof that energy is only half the story, terminal ballistics matter just as much, if not more!

At point blank range with field tips the compound crossbow looks impressive, however at normal hunting ranges their penetration falls off significantly compared to normal compound now with razor heads.

the compound crossbow has lighter draw weight but because it is drawn back much further than the historical one it has more time to accelerate the bolt to a much higher speed which gives it the better penetrating power, there are other reason but thats the main one. All you have to do is watch a video of someone who know alot about crossbow design, thats were I learned that.

Well as the name states, compound crossbow, it puts out more energy than is required to pull it back. The cams make all that possible plus modern bolt design means we can use lighter more efficient shafts that are also more ridged. The modern bolt isint losing as much energy when it flexes on impact given better penetration.

That's a long power stroke on the Chinese crossbow. I think we see the advantages of the compound bow system in this test.

Can we talk about how utterly filthy that scale is?

What would happen if you gave a modern crossbow a draw weight of 1000-2000lbs?

Arrow diameter makes a significant difference when shooting into a medium that has a lot of friction, like driving with the breaks on.

My Ten X Nitro XRT shoots a 30 gram arrow at 440 fps 190ish ft lbs of energy. It will defeat a US kevlar helmet and soft body armor vest easily with broadheads. Love your channel. Velocity is the key. 1/2 MV squared... The sound comparison at the end is interesting. Very nice add.

You should revisit this with actual modern compound and crossbow.

Arrowhead and shaft cross-section makes a huge difference in penetration. Carbon arrows shot even from weak bows tend to go through archery targets that stop wooden arrows easily. For example I can shoot straight through straw mats with a mere 22# modern recurve.

being an archery of some years, compounds accelerate a arrow/ bolt far more effeciently, as it start at less poundage[ ie 0% lett off] building to max just before brace hight, hence creating an equation of math that would be difficult plus time in contact with string etc etc, I don't like to compare, as its unfair, add in for my self, shooting 31 inch draw,, at a 7.5 brace height,, i again gain over a smaller shooter drawing the same poundage, never ending equations

Ran the numbers.. if anyone is interested in North American type energy units : Windlass- 74 ft.lbs... Compound Xbow- 95.4 ft.lbs...Compound Bow- 52 ft.lbs... and Longbow - 28 ft.lbs... That type of energy number is ruled by Velocity... getting hit by a 663 grain Longbow shaft will still completely ruin your day... and all those that follow.

I'd love to see a compound windlass crossbow. Couple the increased draw length with insane poundage and you've got youself a hand scorpion.

Results seem to correspond to energy nicely. Just not momentum. Maybe take energy divided by the arrow cross section.

I would love to see this test done against a hardened leather siege bell. Previous videos I have seen have had period longbow arrows and crossbow bolts (of lesser power) bounce off, leaving the team inside free to waltz up to the gates and deploy their payload.

Suggested alternative title for this video - 'Tod spoils the day of some defenseless inanimate objects' And why not? That clipboard was looking at me funny, it was just begging to be taught a lesson. 😂

What I remember from some other firearms ballistic testing - velocity is a big factor in penetration.

Projectile weight is a big factor. "Muzzle velocity" i.e. the reading on the crono at point blank is a big consideration. Noting that the FPS of the Compound X-Bow is twice that of the historical replica, it does not surprise me in the least bit that the bolt had better penetration, especially in light of the fact it appears to be about half the diameter of the historical bolt, and is fitted with a very thin and sleek modern head. I would suggest that you can draw a loose comparison between these two x-bows and the 5.56 NATO v. a larger, slower cartridge. The modern x-bow is sort of akin to the 5.56. Light projectile able to be propelled forward at higher velocity. And it takes a lot less draw weight in the limbs to do it.

It's a great test! I would say, that it's not momentum which goes with penetration, but kinetic energy. Momentum would be important if you want to estimate a velocity of a man just after he was shot with this stuff. Kinetic energy will transfer to tissue damage. So with many simplifications- more energy = more penetration and destruction inside :)

You'd need to divide momentum by cross section for penetration. The arrowhead shape and shaft friction also matter.