I would like to know how certain bows can be faster at the same draw weight.

I am fortunate enough to own a used Border recurve (53#) and I know it is known as a very fast bow. I also got an ILF recurve of identical draw weight and set to the same brace and I can feel the difference in speed - the Border just nails them!

What I can't figure out is how this happens. It seems like once the 53 lb force imparts its stuff on the arrow it should fly just as fast with either bow. If the limbs were much heavier with one of the bows then it would make sense that they would spring slower. But the ILF limbs are lighter than the border's, if anything.

The other thing I notice is that the re-curves at the tips on the Border are much more pronounced than the ILF. It seems to make sense that they would pull the string harder through to the brace as the string "shortens" on the curves.

Sorry if this has already been debated or explained ad nauseum in other threads - maybe someone you can quote me a link if so. When I did a search I only got threads that argued about which bow is faster and why you want it in the first place, not how it occurs.

I'm going to follow this one close.. I've been really paying attention to this issue since I started having shoulder/strength problems.

I know that draw weight is far from the whole description of a bow. I have been getting many bows in the 35 to 45 pound range. I know that, for instance, i can pull 38# comfortably on some bows, but have trouble with 35 on others, and on some, I can't pull 35 at all. If I do a power curve graph on the bows, what I find is that the "stiff" bows, which usually do seem faster, build up their power curve much earlier, so that over the total draw, I'm pulling a greater total amount of weight.

Now, I'm no bowyer, and I suspect it's far from that simple... limb shape, curve, thickness, length all have to be a part of it, but I do know that for me, fast is just not a prime criteria as compared to a smooth, even build to the draw. In this respect, I find that Super Kodiaks (old ones) rule. I can still pull (on a good day) a as much as 43# on a SK. I recently sprung for a hotshot new bow that was noted for speed... it was only 37#. Beautiful thing, but I could no more pull it than I could fly. (Note: all of these weight references are adjusted to what I pull on the bow with my very short 25" draw)

So, where the power curve starts to kick in is at least one key factor.

Limb length seems to be another. I had Gary Sentman build me a bow at 35#, 25". First thing he said was that he'd have to make the riser a bit longer to shorten the limb so I had some speed at that light draw.

I'm real interested in what comes up here. When you get down into the low 30's range, which is where I'm headed, you need all the speed you can get and I know that this is an issue I'm just barely beginning to understand.

Thanks for starting this one, Zog

Hey guys, not sure Ill answer this one the greatest but I'll give it a go then get Badger in on this one.

Alot of different factors involved here. first, string weights are huge factors in bow performance. two bows the same pull weight one with a lighter F/F string no silencers and then the other one loaded to the hilt (brass nock point and puff silencers)will not be near as able to recover to brace as fast carrying more weight.(most of the time) second is outer limb weight. the lighter the last 6" of limb the faster that limb can recover to brace. the overall design is another factor, how a limb is optimized using its bend and profile can play large parts in how efficiently a bow functions. preload in the limbs to brace the bow can be a factor as well. more early preload to get the bow to brace means being able to use lighter cores(again less moving mass) but then stability issues can arise if there is too much. alot of delicate balances in bow design for getting the most out of them but not giving up the shootability. Basically what it boils down to is how well each bow design & setup as a whole is able to recover its stored energy - string weight,tip weight,design etc..and put that energy into the arrow. Ken

I don't think I'll ever be able to figure this out completely. I've learned there are many factors that come into play when you release the string. It isn't cut and dried. I'm still trying to fiqure out why some 50# bows feel like your drawing back 60# and some 60# bows feel like 50#.

M Style,

Ok as long as Im back I'll try that one too.

One reason that a bow feels heavier than its real draw weight could be that it is a shorter bow with a high string angle at full draw almost as though it is pinching the fingers together. another could be that the bow is stacking at your full draw and limb to string angles play a part here.

On the other side when a bow feels lighter through the draw or feels "smoother" to pull the bow is probably designed well as to be using most of its draw weight earlier in the draw cycle. Early string weight, meaning that the bow gains 3 to 4 pounds per inch in the first few inches and then maybe in the middle of the draw is gaining only 2# per inch out to the persons full draw. This type of bow will be better in terms of overall performance also.

Ken

Some bowyers are able to build limbs that store more energy than others-I don't so much care 'why' but I do care 'who'. I have 2 ACS bows and my young son has one too. They are smooth and very fast-there may be faster. I was able to drop from a decent 58# recurve to a 49# ACS and not lose any performance (speed). Anyway if you go to their web site acsbows.com, you will find a discussion on stored energy and speed.

LOL, Me too Ibex! :)....Lots of things in play and most have been covered but in a nut shell one bow only shoots faster then another if it stores more energy under the f/d curve, is more efficient, or both..The "how" part of making a bow store more energy or be more efficient is the hard part. It's easy to take things too far. All of the best performing bows will have stiff tips in some way shape or form. They might use reflex, or a reverse wedge, or sharp hook recurve, static tips, ACS, or a combination of several. They're all methods trying to do the same thing.

One interesting thing, you could do d/f curves and performance data on 50 bows, pick out the top 10 and they'll be mixed longbows and recurves and you can't pick out which are which by only looking at the data. All bows function the same under the laws of physics be it a green willow limb or the latest greatest compound. It's nice to be able to shoot 40 pounds and shoot the same arrow the same speed as another shooting 50 or more. It's also nice to watch a "longbow" flight bow out distance compounds, saw that last week end! :)....O.L.

Bjorn, On average the ACS bows store less energy then most recurves, they make up for it in efficiency. I'd kill for another .1 or .2 se/pdf! :)....O.L.

Zog, have you read the Traditional Bowyer's Bible's section on bow design and performance? That is a good place to start, tho there is more info out there. There are some differences between all wood bows and fiberglass bows, but when you get down to it those differences are mainly di9fferences in what you can get away with without the bow snapping, rather than actual engineering and design issues.

Basics, to store more energy;

higher draw weight, longer draw length, longer limbs, more material bending more stiffness, more leverage to help bend that material, more elastic and stiff material, high early draw weight (lot of tension on the string to brace), things like that.

The main impediments are:

Loss of leverage, low stiffness/high weight ratio in limbs, high mass in parts of the limb that must move far, material failure (set or excessive string follow), mass due to material,

Poke's last post is a good example. The limbs on his bows store less energy than many recurves, which are (over-simplified)more stressed-up and have high leverage applied to the rest of the limb by the recurves. However, his bows beat any of them in the category of stiffness to weight, especially because of where his limbs get the stiffness from (the cross section rather than just thickness and width). So the recurves' ratios of stored energy/draw weight are favorable, but the Adcock cross Section beats 'em cuz so little of the energy stored goes to pushing the limbs back to brace height. His limbs are so light for their stiffness, esp. where it counts out toward the tips.

A long bow stores more energy, but if a bow is too long, the energy is wasted moving the long, heavy tips. A recurve provides leverage to help bend stiffer limbs more easily later in the draw, and give high early draw weight, but they must be stable or energy is lost to vibration, the materials might fail, or the recurve might add too much mass.

And the actual execution of the bow itself; the care in craftsmanship, balancing out concerns during the design, and careful tillering, make a huge difference.

Radical Limb design is what Schafer told me many years ago, at that time Silvertips were amoung the fastest. Maybe Dave can chime in on this one. Compare the bows made in the 50s unstrung to the more faster bows of today there is less curve in the limbs in most of the 50s bows.

Billy

Pretty hard to add much to some of the posts above but both Ken and Poke brought up something interesting and true. The highest energy storing bows are seldom the most efficient. Also as said above you can take things too far sometimes but just in the name of science or flight shooting it is good to know what these bows are capable of doing. One factor that I think is ignored but tends to play a big part in the high performance of well made longbows is the lack of vibration they have or limb distorsion durring the power stroke. This can get a bit into theory at this point which is not always reliable but once we start hitting 90% efficiency and above we have to start looking hard at where this extra energy is comming form. I checked some stats on one of Kenr's bows above, he calls them whipper sticks. This was a fiberglass version of his very fast carbon longbows. Stored energy was not extremly high but decent at about 87% but efficiency went through the ceiling at 92%. Tiller and design had virtually eliminated all vibration and limb distorsion. I believe that extremely light outer limbs not only accelerate faster but at the right time are also able to decelerate when neccessary to allow the mid limb to keep up with it for better overall limb timing. Lots of folks on both the modern side and primitive side are putting their heads together these days and some real good things are happening in the world of long bows and recurves alike. Talk about light bows, a couple of years ago I was shooting a 42# adcock bow and it was hitting I think 242 fps with a 300 grain arrow shooting fingers. Thats a real flat shooting bow!! Steve

"but in a nut shell one bow only shoots faster then another if it stores more energy under the f/d curve, is more efficient, or both..The "how" part of making a bow store more energy or be more efficient is the hard part"

I think this is one of the most misleading concepts rampant in archery, the Norm Mullaney effect. I think this comes from the fact that at any given time, most of the bows are relatively similar, and if you look at two force draw curves the one with the most area under it is highly likely to be the faster bow. Or if two bows have identical curves, and OL's is the faster, then the other one gets dismissed as less efficient, which is obvious but not very descriptive.

My theory, which is true, but not believed by anyone I have ever met, is that what makes a bow fast is the ability to get a string moving faster. I first came to this conclusion when thinking about compounds, thoug it applies to sticks also. For the same peak draw weight the average compound stores more energy than the average recurve you can't get stuff moving without the energy to do the job. But the real key to compound speed is that the pulley effect moves the string 2 inches for every inch the tips move apart. There are losses, you don't get everything, but that is the speed advantage right there. It's massive. And I also think there is a correlation between the amount the string moves and the energy stored. Making cams and such affects the shaped of the force draw, but it also affects the rate at which string is picked up. The faster you move that string, the faster the arrow can go.

Each material has a basic speed at which is responds to deflection. At any one time, limbs are made of much the same material, and just about as well by different manufacturers. But any differences that allow limbs to move faster will likely move the string faster, and that will move the arrow faster. This can be done with no change in the underlying force draw curve. So limbs make of wet saplings will be heavier than ACS and not recover as fast, even if the underlying F/D curve is identical. So techs like carbon, foam, or acs that bring with them lighter tough limbs will be faster.

Limb design is also a factor in the rate the string is moved. Take the stiff tips OL mentioned, they move faster because the main bend is further away from the tip. Whatever rate of change the lower position bend is capable of, it will move a string faster if it occurs nearer the handle. An example is something like a lacrosse stick throwing a ball vs. an arm alone, even if of the same overall length.

Another point is the timing in a limb or system. Any time there is a timing problem string is essentially being fed out and in at the same time, or just not fed in when it counts. Slower string movement means less speed. This is a bit like releasing the club at the top of the swing, the extra speed of the release is added before the ball is hit. The same thing happens with active recurves, though not as efficiently in net as some other designs.

I think the best way to think of speed is that speed, not F/D curves are it's source look for stuff that makes the string move faster. If nothing else, knowing you need more area under the F/D curve merely prompts the question "how do I get that?" If you think of the system in terms of just speeding up the rate at which the string is moved, that's something that you can use your very next tillering session. Speaking of which, I am still indebted to OL for bailing me out when I was in the sticky stuff while tillering my 3 piece.

By the way, It sorta works in reverse also. Anything that speeds the tips and string up should be looked at skeptically when looking for stability and accuracy. It may not be as simple as that, but for example, loose limbs with stiff tips that get the tips moving around a lot may not track the tips as well as another design. But who cares, we don't have an industry standard measurement for that.

Here is an analogy, probably not perfect: The bicycle.

- Finite amount of human energy, think energy under the F/D curve.

- Maximum efficient speed, each rider will only be able to pedal efficiently at a given RPM, speeding it up isn't easy, or efficient. Just as every limb material has a fixed recovery rate.

- Gearing. A more powerful rider will not be faster than a less powerful one if he doesn't have the right gearing to take advantage of the power. Similarly, a compound with pulleys can move string faster for a higher optimal speed, remember the 6 wheel compound? It wasn't the ultimate solution, it didn't affect F/D, or let-off, they knew what they were doing. There are factors for sticks also, see above.

- Efficiency of materials, lighter wheels in particular. Lighter strings and limbs for bows.

- Timing, stuff like goofing gear changes or anything that leaves you spinning your pedals will not enhance your speed. This correlates to wheel timing on compounds or tiller problems on sticks, possibly active recurves also.

Bowlin, A lot of things are not as simple as they seem on the surface, Compounds store more energy than simple bows not because of the cams but because of the pulley's. Compounds are becomming more efficient but for the most part I believe conventional bows are slightly more efficent on the average. Just having light limbs will not initself guarantee high efficiency. Bows can absorb a lot of energy that should be going into the arrow. Looking at which bows store the most energy is also a poor indicator of how well the bow will perform. You can't take a design very far into energy storage before the efficiency starts rapidly dropping making it counter productive. Too much of the limb mass becomes dedicated to stablizing the limbs instead of propelling them. When they become wide and thin they become subject to increased vibrations and distorsions. The better hybrids today seem to have the best of both worlds, decent energy storage and high efficiency. The better recurves have high energy storage and decent efficency. Lots of guys out there know the secret and are willing to give out hints but just not exact details as they worked too hard figuring them out. Steve

I think that you are comparing apple and oranges. What are the arrow weights. The FITA bow is made to shoot light target arrows, a 53# FITA should shoot target arrows over 220 fps. Not too sure if the Border shoots that fast with arrows in it's intended weight range..

Small light tips, thin light strings, small light string silencers and light arrows all add speed, and nosie.

cast is what you are wanting to improve with any bow design. i make wood bows and to increase cast several factors must be addressed: one, limb tip weight must be reduced. i keep mine around 5/16 wide. if any part of the limb is not working then it's getting a free ride and robs energy. second, design, r/d type bows store more early draw weight compared to straight limb bows. the perry reflex as well as the duo-flex flight bows store tremendous amounts of energy. third, the further the tips are beyond the grip unstrung more energy is stored and available to be transfered to the arrow. this can be seen in the turkish flight bows or crab bows where the tips actually cross when unstrung. static recurves take advantage of this fact but tip weight can be a problem. i've seen all this in my bows. i had a static recurve that was 52#@28 that shot a 500gr arrow 176fps and i have a 55#@28 straight bow that shoots a 500gr arrow 159fps. it's all in the design and materials. glass bow builders can get away with more in design that wood bow builders. of course all this is just my opinion and subject for further debate.

Years ago, I made a 66" longbow that was designed for speed. It was 72#@28" with black locust, .050 black glass, .006 tpi, 2" reflex, deep cored, narrow limbs. The handle was 19" long. No overlays, tiny tips, fast flight sting, no silencers or nocking point. With a 28", 500 gr cedar arrow, it crono'ed 226fps average with fingers. With a 700 gr ramin arrow it averaged over 205 fps. After a hundred shots or so, the bow lost poundage and speed. It was hard to shoot. It seemed to magnify mistakes. It worked great for ariel targets though.

Chuck

It's all in how it is made and the material used. A real simplistic way of looking at it is to pick up a 55# rock and then draw and shoot a 55# bow. Or something closer to a bow , use a tree limb that takes 55# to pull it back. like in everything else there are ways of doing it then there are more efficient ways of doing it. Randy

Bowlim, "I think this is one of the most misleading concepts rampant in archery, the Norm Mullaney effect." Misunderstood, yes...Misleading??...No.....Most could be lead by the hand and they'd still never "get it" cause they've been mislead by others over 60 years and much of that in books. Look at comments like .006 tapers and thin tips above! :)

So, all your theories on how compounds work...Tell me exactly how the arrow knows what kind of bow it comes out of? All it knows is how much force is applied for how long. Cams maintain a higher average force over a longer distance is all they do. A good recurve or lb that stores 53% of potential compared to another at 50% is doing exactly the same thing. A good recurve will have an se/pdf of about 1.0 and a compound about 1.3. Like Steve said too, good recurves or longbows are as efficient or more so then compounds, they just don't store as much horsepower....O.L.

O.L., what do you mean about the .006 tapers and thin tips?

NC, Was just responding to a fellow describing a very "whippy tipped" bow which is exactly the WRONG thing to do if performance is desired. Does no good to reduce tip mass and lose storage in the process. Too many folks reading TBB's as gospel and forgetting the laws of physics....O.L.

OK, Pokenhope...how does a bow that you see as "wrong" produce such high arrow speed? Lots of people witnessed this at several different crono's. Fact is; a very deep cored longbow with a high wood to glass ratio, still has plenty of mass at the tips. A fast taper allows the limbs to recover faster on a longer bow. Notice that I got almost 210 fps with a 10gr per pound arrow. Can any of the reverse taper fat limb tip bows do that?

I don't see any of the super fast designs as being much of an advantage. I won most of my shoots with a 160 fps bow and heavy arrows. I'll take consitancy anytime.

Instead of being too complicated I will give it in laymans terms. The faster the limb returns to its pre drawn position the faster the arrow is off the string. Poundage can be exactly the same and limb shape, makeup of materials ext greatly effects how that poundage is used. Efficiency.

Basically the lighter the limb is for the poundage it pulls and the shorter the working area the faster the limb will return. However the working area cannot be made to be so short as to effect the longevity of the bow by taking all the strin all the time.

Compromises and a little here and a little there. To me its a lot of little things that make the difference in a super fast bow and one that is fast. Details

ps. a light weight tip can be accomplished and still be stiff. this helps to accomplish fast return which is basically less foreward mass movement. Super fast bows like Kens have limb tip wedges and still have little tip mass. they generally have long risers\ fades or power lams. think on it like this. If I can design a limb profile that will allow me to make a 1 1/2 inch wide limb only 200 thousands thick instead of 300 thousands thick and be the same length and same 55 lbs the weight of the 200 thousands thick limb is going to be less than the 300 thick limb and still it is the same poundage. That difference in weight is applied to foreward return speed. This in turn is applied to arrow speed,. At exactly the same draw length and exactly the same bow length and the same arrow weight the bow with the 200 thousands thick limbs will outshoot the one with the 300 thousands limbs in all ways. There will be less shock, less vibration,. faster arrow./\even though the poundage of the bow is exactly the same as the one with the 300 thousands limb.

There are other factors that contribute to fast bows but in my estimation limb weight for a given length and speed is the great differential.

Some accomplish this with design, some with materials, some apply both and those are the really good , fast bows.

Chuck, too bad you still don't have that bow. We have an annual walk the talk event for all us guys that like to brag up our bows, All in good fun. We send our bows in for a formal testing under equal and controlled condition. Each walk the talk the conditions and testing methods improve as we gain experience in testing. Steve

A pound is a pound

Babysaph, a pound is a pound when you are drawing the bow but a pound is not a pound when you let go of the string. Steve

That's for sure, Steve. As I said, I own two 62 inch 53 lb recurves. I shot them one after the other and one is definitely faster than the other.

Chuck, I'm not saying you didn't "see" the numbers you saw. Other then the 2" of reflex a high taper like that makes for a whippy tipped bow alomg the same lines as a Hill bow and we know what barn burners they are. Narrow and deep is correct for the tip as long as the mid limb is wide and thin! :) Typical numbers for longbows erred to their benefit at 28" is se/pdf's in the .95 range, 80% efficient which is also high would give you 54ft/lbs in the arrow. You got 57 with the 500 and 65 with the 700. That's a 13% spread and too wide for one or both to be correct. And that's guestimates in the bows favor, typical real numbers would be several notches lower. At 9gr/lb@28" the fastest bow Norb Mullaney has ever tested was 203-204 off the machine, Blacky with fingers about 193...I caught a 12lb bass in a tournament once but for some reason it only weighed 7 on the official scales? :) Not saying there might be some faster out there but if there is for some reason they won't hand them to reputatble third parties....O.L.

I guess 4 different crono's were wrong. Even though it out shot same weight Black Widows by 20 fps on the same crono's with the same arrows. Chuck

Chuck, no offense but that's the way bows "work". You won't see more then 5-6% difference 7gr/lb and 10 with any bows unless something is amiss and those that understand how bows work and have tested a lot of bows would catch numbers that aren't following the rules and determine the source. Chronos are great, just like a tape measures they are very accurate. I've got the wrong measurements before on a ruler, wasn't the rulers fault. The only problems chronos will have is in poor lighting. Draw length, bow weight, arrow weights, lots of places for error. A little bit in each one becomes a lot. Not saying you didn't see what you saw, but this is the parking lot, not the race track! :)...O.L.

Chuck, I had a friend come over to check the speed of his bow once. We measured the depth of his handle and figured a 28" broadhead would be perfect as we could not overdraw. Shot after shot I got 202 fps, now he tried the bow and shot after shot he got 182 fps. Thats 20 fps difference. We put the bow on a shooting machine and got 188 still very fast but not 202. The story is a handshot reading just doesn't mean too much unless you shoot a lot of bows over a chrony and have yourself calibrated to your shooting machine. I think the design you described is very well capable of some good speeds, I have seen similar primitive designs by Tim Baker that performed very well. Steve

A person that truely wants to be accurate can. But many due to pride, ego, or what ever can't be. That's the reason you'll never hear me say I got such and such out of one of my bows. I let Norb, Blacky, and flight records speak for me. When folks come over and we chunk arrows through a chrono, the numbers get covered up cause if you don't every shot will get just a little bit faster. These forums are just parking lots at the race track, you won't see the checkered flag in the parking lot. The mechanics for the best cars we can learn something from, unless we're smarter then them!........O.L.

While we are here doing this, anyway, I have an interesting question.....

Currently obsessed with the Holmegaard design and mentioned it on another thread. I am somewhat convinced that the outer limbs were not narrowed just to save mass. I am sort of theorizing that they were in fact made rigid for leverage, and that it logically follows that they then would have to be made narrow.

In keeping with some posts above, I think the ancient bowyer may have been trying to get performance by making a thin, wide, very stiff limb section easy to bend by attaching long levers to it. This keeps the actual bending to a minimun, because a little bend produces a big tip movement. The inner limb is really stiff, but wide and not too deep, also keeping set to a minimum.

All stuff you guys know, I'm just saying that most of the reding I've done sez the Holmegaasrd was designed that way because the bowyer wanted light outer limbs and then made them stiff, or, they would get whippy and take near-tip set. I thiink he apprioached it fromt eh o0ther direction. He wanted long, high-leverage outer limbs and had to narrow them or he wouldn't gain anything. Just the other side of the coin.

Just noticed this thread and though that I would throw a thoughts around. I'm the owner of Border Archery BTW and therefor have just declared my self interest to be fair to everyone.

Border have been making ILF target limbs for decades and held some olympic records in the past. In 2004 we had a couple man and wife team compete in the World flight comps in the US and with the new carbon bows, new at that time, they took 12 gold medals and set 6 new distance records and some still stand today.

Zog not surprising your Balck Douglas is fast!

Looking at accuracy just check out /www.archery-interchange.com/forum/border-archery/19274-stock-limbs.html. This has just been posted. This guy is from the US and has tested the top ILF limbs. Read his results!

Speed does not come from one simple facet but multiple. If it were easy all limbs would be fast and stable

Sid

Springbuck, "I am sort of theorizing that they were in fact made rigid for leverage, and that it logically follows that they then would have to be made narrow."

Absolutly...Reflex, recurves, scyas (sp?), properly made Holmgaards, static tips, ACS, are all doing the same thing, increasing the stiffnass of the tips which provides a "lever" type function. The current 50# primative flight record holder did it with a Holmgaard on steroids.

Sid's correct about multiple facets, many get 1 or 2 things right, then screw up 4 others for a net result of zero. The highest performing recurve we've ever tested to this day was a Border Black Douglas and we won't mention who or what bows took several of their records away from them! :)....O.L.

Oh, The highest performing ILF limbs we've tested were Border's also, beat G3's and WinWin's by 4-5%. Sid and his boys are doing thing right...O.L.

There are some things that have not been mentioned that I will mention. Timing. initial draw weight high with even draw curve through entire cycle, tuning, ect.

Everything is summed up in the return speed of the limb though and I still maintain that physical weight is the greatest contributing factor/ Second would be return properties of materials used. I really believe that this may be the greatest overlooked factor with most bowyers. The stiffer and lighter the materials used the faster the bow if all other factors such as limb design, string , ect are same./

A lb is a lb to draw but as Steve said it certainly is used differently with each bow. put a 375 hp engine in a caddilac and put one in a Lamborgini. Get the point?

Cedarsmyth, Yep, no doubt but one of mine won the IBO Worlds TH class a while back against FITA recurves. How many Hill bows do you see in the TH class if they are so easy to shoot? This thread was about performance, of course they have to be "stable", goes without saying. Got any "performance" suggestions?....O.L.

I know a lot of you "traditionalist" are anti "performance" as if it's a bad word. Performance crosses directly to draw weight and that's on top on everybodies list when selecting a bow. What performance does if paid attention to is allows that lady or kid who can't draw 95# to participate be it trying to reach 90 meters with a soda straw or shoot a 55# recurve for buffalo cause it shoots the same arrow as hard as a 75# Hill. I assume the anit speed folks are all shooting 15# green willow limbs for griz cause if your not, you to care about performance whether you want to admit it or not.....O.L.

Sid and O.L., you both make great bows, I know, I have one of each, but leaving design aside for just a second, what material properties do the most to accelerate the limbs the fastest, and are there any other areas of technology research going on that can be incorporated into the limb evolution?

I'd like to see what a Holmegaard on steroids looks like. I'm tinkering with the design a lot myself.

The part from Sid and Poke is exactly what I wans talking about about "good execution". Making good decisions about compromises and balances, then making that happen well with few mistakes.

Sixby, I mentioned high early draw weight! (Sniff!) I can't believe nobody noticed.

I don't think it is anti-performance, exactly, but I think some people think that some of us put too much emphasis on speed. But, people do use O.L.'s bows for hunting....

My own little "hobby" within the hobby is looking for high performance in a hunting bow made from natural materials. I love studying and understanding different aspects of design with primitive bows and then copying, shuffling, combining, and improving features, just to tinker. I LOVE the mental exercise and the tinkering and working with wood and tools.

My personal Holy Grail is a rugged, accurate, reliable hunting bow that shoots 10 GPP arrows as fast as a wood bow can.

Dumb question -

Do bowyers have a way to measure hysteresis?

SDT, Yes, It's the difference between going up draw weight values as opposed to going down draw weight values. In glass bows it's typically about 1% and nothing you can do about it anyway.

Cedar, I think it was the same year they won both longbow and recurve class at Cloverdale. What brace height did they have? They don't move around as much as Olympic recurves so that must be very important. How did your bows do?

JusPassin, Can't speak for Sid but the indistry doesn't have as good a carbon as we could have, all we get are spin offs from the aviation industry which is geared for ease of use and cost as opposed to best mechanical properties. Sid makes their own carbon. Ceramics might hold some future but carbon nano tubes looks most promising. Their only about $300 a gram right now! :) Maximum stiffness with minimum mass, the requirements haven't changed for 60,000 years....O.L.

String.D.T

The only way Ive been able to measure it is just by video from a side profile out of my machine and then slow it down. Not the greatest method given the technology Im dealing with, but you can guage it some and then compare changes in your designs. But again hard to tell very minor differences when you get right down to final designs making very small changes. Not a dumb question at all, and I think a very much overlooked aspect of "building a better mousetrap". Ken

String, hystreisis as it applies to bows and arrows is mainly reffering to internal friction of the limb material. In general synthetic materials have a negligable amount. Wood is reported to have as much as 10% and as little as 5%. One device used to measure hysterisis is a simple method where you take a flat piece of the material and simply bend it down to a premeasured mark and then release it measuring how far it goes, we usually use an aluminum can as a clicker as we can hear the slight click from a small contact. Most woods measure at about 10%, dry bamboo I think measured at 10% if held one way then 5% if reversed. MC of the wood is a factor in how much hysterisis is in the wood. If memeory serves me right woods like black locust and purple heart scored well here and they are also woods that tend to chrysal when used in bow making. All in all there was not much difference between woods. I am not convinced that this method of measuring hysterisis is of much value in figuring how much you will actually have in a shot bow.

Possibly missunderstood in my last post and just for info purposes, - what I am refering to is hystresis the way Badger describes it where we are seeing how far a limb physically travals past brace when released (excess vibration)or(lack of vertical stability) I was not refering to it in the sense that you measure the force draw curve on the way up and then on the way down and then getting the % of difference. sorry for the confusion

Ken

Ken,I am just looking at raw materials. You build kind of a diving board, if you pull the flat pice down say 6" and then let it go it should go past the center 6" for zero hysterisis. Nothing relating to bows at all. Just a material test. Really irelevant for modern materials anyway.

Ken,I am just looking at raw materials. You build kind of a diving board, if you pull the flat pice down say 6" and then let it go it should go past the center 6" for zero hysterisis. Nothing relating to bows at all. Just a material test. Really irelevant for modern materials anyway.

Ken,I am just looking at raw materials. You build kind of a diving board, if you pull the flat pice down say 6" and then let it go it should go past the center 6" for zero hysterisis. Nothing relating to bows at all. Just a material test. Really irelevant for modern materials anyway.

OK Steve, I get it!! (LOL)and yeah I know, you taught me, remember? (LOL)

I wonder if Fred Bear & Howard Hill ever cared about this "SPEED" thing ......... Nah ..... I doubt it ..... They just went out & got "er" DONE ...

I got over 220 fps (it was about 15 years ago, but I think we got 227 fps) once with a HH bow...I really did.

Needless to say it was a 75#@28" bow drawn to about 30" (I don't know how far we drew it, but it was well past 28") shooting about a 500 grain carbon nitting needle for an arrow. LOL

I have seen MANY people play in chronos and I have done it too. One thing I have often see is people report their bows about 20 fps faster than they really are...because when they shoot through the chrono they often draw about 2 more inches than normally. Oh, the pride and competition gets to us all.

In the end though, I have given all this stuff up and accepted what I like (which really are very efficient bows shooting around an honest 180-185 fps with about 9 grains per pound with fingers with an honest 28" draw. I have one bow here that I truely believe will do about 190 with 9+ grains per pound with a 28" draw (a very prestressed design at brace but also a very stable shooter). That bow is only 62" long, has a whopping 23-24" riser from tip of the fade out to tip of the fade out and has 2 inches of reflex in the fairly radical r/d limb with relatively small limb tips. It is also reverse trapazoid limb (since tension is stronger than compression the compression side should be wider than the tension...as adding more to the tension side of the limb is pointless...despite nearly 90% of bowyers doing exactly that). Still though, I have found myself picking up a self bow of all things lately...and enjoying it.

Also, no one can really give OL any crap. His work has proven itself to be the real deal. The man obviously knows a little bit at least.

BTW, that same 75# HH bow typically shot a 600 grain arrow only about 180 fps I think...and that may be on the generous side. I don't recall exactly, although I do remember Byron Fergusson shooting with me once and we both got 184 fps...but I just can't remember what weight arrow that was. For some reason a 2219 comes to mind, but I don't recall the tip size (125-160 + insert I imagine). Anyway, that was years ago. Today I have a 63# HH bow, and I enjoy it. It might only get about 175 fps or so. I don't know what speed it shoots even though I have my own chronograph for testing various loads in bullets because it really doesn't matter to me what that bow shoots. I got over all that stuff long ago. Efficiency is beneficial no doubt, but enjoying what you shoot is also benefical. I don't shoot the HH bow for efficiency but for the enjoyment of traditional archery...so I got one like OL said with enough umph behind it to do what is necessary.

Any of us that REALLY wanted efficiency would probably put down the traditional bow all together.

Recurve - v - Longbow speed

OL; When we brough the black Griffon out again about 4 to 5 years ago(and please remmeber it was designed as a clasical longbow and competition legal) I though we had cracked it the best and fastest. At that time we did not know of OL Adcock but became quickly aware as archers were arguing which was faster/better. While close I have to say not close enough and the GL was a rapid response to the OL challenge. Easy to copy ideas as we are outside the US patent but we won't copy but we have been inspired to do better and that is down to you and your creations. I've had archers say if Border an Ol could get together what would transpire and I have often though that. If you have big enough workshops we would seriously think about coming over if the invitation was mutual. We produce about 1000 bows per year at present and stuck as we have exhausted all the space we have.

Just look at the Pete Ward site and you will see a test/review on a modern metal handled recurve with modern top of the range carbon limbs. If you compare that with another review the Griffon GL you will see that the speed on light-weight arrows are similar for both bows but the longbow out performs the Carbo recurve on the heavy weight arrows. Allowing for differences in bow length between various models (Longber bow-length longer limb heavier mass "usually" and longer and therefore heavier string to propell and so the longer bow is generally slower for the same bow length). You will see that the Griffon and OL bows also tested on site have similar speeds. Also bear in mind that the Griffin GL is designed to conform to a classical "D" when at brace height (competition legal) and no stored energy advantage from an obvious reflex showing at brace height on the shorter OL bows.

There is no way around the fact that recurves store more energy and so the only way a longbow can overtake a recurve is when stored energy levels are at maximum for a longbow type design and limb mass is significantly lower. These two naturally fight each other as higher energies neads stiffer outer limbs as OL says but that generally means higher mass and at some point a crossover occurs. The recurve will always be smoother as the recurve gives an added bend couple to the limb. Ther is a reduced smoothness the shorter a longbow gets. The same applies to recurves but the bows can be made much shorter before this happens to the same degree. Smoothness and storred energy are the same bedfellow. I was always aware that a well made carbon longbow would match most glass recurves but in the PW evaluations a comparision can be made (not exact I have to say) suggests as good as and possibly better than some carbon made recurves. That did surprise me! It was the other Sid here at Border that noticed that.

One point OL refferes to the tests done by John Havard on HEX4 giving an almost AMO of 197 fps if I recall well, arrows were over heavy by 5 grains. This was done nearly 5 years ago. Since then we have introduced the new laminates that are around 200 grains lighter and double the torsional stiffness and so that must put the equivqlemt limb today at 200fps and the HEX5 above have more stored energy.

This thread is about speed it started that way however as a limb moves away from the continuous curve (at brace height) to more and more reflex until eventually becomes recurved and on to advanced recurve the bow naturally becomes more and more unstable unless the bowyer does something extraordinary to stabilise it.

The archer's paradox starts and is initiated by the release hand and the more reflexed the limb is (as shown at brace height) the more unstable it becomes. The more sensitive to shoot and so Hill's observations quite naturally are correct! As in all things arechery a real gain in one area brings an almost equaly disadvantage. Modern materials however give us the chance to address some of these dissadvantages without too much added mass penalty and so more advantage than dissadvantage up to certain limits.

However I must stress in this speed crazzy world that the most vital element is stability and it seems to be forgotten by all but the most experienced archers. We go for stability first and any speed is a bonus. Howard Hill advocated that above all else.

To answer those who say that HH was not interested in speed he was one of the very first to add that new-fangled product Glass Fibre to his bows. And so today nothing has really changed other than the speed of the bows.

Speed and our quest for it!

A couple of thoughts. Back in the 1970's and 80's when I started shooting, dacron was the advanced string material then and aluminium and glass fibre were the arrows. A 2216 was a lightweight shaft at 8 Grains Per Pound

Today it seems that almost everyone has shoulder problems and I don't recall any one with shoulder problems back then it was never discussed and so what has changed?

Well I can think of two fundamental changes that have rocked bow performance and arrow speed.

FastFlite has appeared! When it first arrived on the scene it snapped nocks off and broke risers. Bow limbs were reinforced and so were the risers and where does that shock go now. The bows have been reinforced but archers are still made of muscle and bone. Many archers now are also shooting arrows down to 5 and 6 grains per pound of bow weight. And we the makers are motivated to get the bows to handle these minimum arrow weights. The 5 GPP is certainly a dry fire and will reduce the life of the bow but that unused energy again goes back into the archer. And that residual energy is 10% to 12% greater on every shot made. It's only 10% some would say but it is enough to break a bow.

We had an R&D program, a German archer 31" draw shooting a 62" Reiver 100lbs bow at his draw length shooting for over a year and a half with arrows 5.9 grains per pound. The bow shot well over 5000 arrows in that period arrow speed was 244 fps and reducing arrow weight did absolutely nothing for arrow speed the system was flat out. The bow eventually failed as we expected it would. That 10% to 12 % eventually broke the bow and so what was it doing to the archer????

Olyimpic target bows are heavy to hold with sights and stabilisers and that added mass to the bow will reduce the jarr from the bow and defend the archer using it to some degree but for hunting bows?

Don't know if these are linked but worthy of thought. I'd rather hunt sharp, hunt hard and hunt close than ruin my shoulders. If for no other reason than to protect myself I would prefer to stay with at least 8 GPP. Personally 9 to 10 GPP

The other issue is that like F1 racing cars the closer to the edge of maximum performance you get the more you will reduce the working life of the bow and perhaps your archery career.

A though for this speed day

I've enjoyed all the insight folks! You guys are a treasure trove of information. It's a great sport where information is shared freely to everyones benefit.

Sid, If the numbers you had were 197, that had to be for 28", my old notes shows AMO of 205 (30")which fits in with the best of the best. The BD also had the highest se/pdf we've seen to date. Yep, there are a lot more ways to screw up the stability of a bow attempting to gain performance then right ways to do it but to hear some talk about the "stability" of straight limbed longbows, recurves should be totally unshootable! And we know that's not true. I see arguments of accuracy and stability used as detours from non-subjective hard factors that can be measured therefore can't be argued. Kind of like the democrats, change the subject to touchy feely stuff when hard facts hurt! :)

Fact is there is a big difference between the best performing bows and the worst. Some do have better shooting qualities then others but that too is subjective. It still comes down to folks shooting as many different bows as they can and make up their own mind what will work best for them. I've yet to find a poor performer that had excellent subjective shooting qualities but some like internal injuries I guess. Again listening to the logic of some, the most accurate "stable" bows should be green willow limbs!

It wasn't very long ago if someone asked if a bow that could only be defined as a "longbow" could ever perform as well as recurves I'd have said no way. Morrison, Border, Black Swan, 21st Century, and others have been proving that line to be blured if not erased. The great designers back in the 50's and 60's had a fork in the road between "longbows" and recurves. They all took the recurve fork putting little to no effort into longbows for whatever reasons. Add to that peoples preconcieved notions and organizations setting rules that don't allow the potential of longbows to be seen. I believe they took the wrong fork. I think longbows have the potential to perform as well if not better, will be more stable, and more pleasant to shoot than recurves. We have to throw the books away and put much of the misleading "common wisdom" in the round file where it belongs. This other fork in the road is fun. Cause there aren't any ruts or potholes in it! :).....O.L.

"The bowyers there really took notice of how the bow reacted after the shot on video and how that action possibly related to both speed and stability."

Cedar, I know you think this is important however the best FITA recurves noodle and shake something terrible and no one can make claims they are not accurate or have poor shooting qualities. The arrow is long gone before any of that goes on. I've seen folks grab recurve limbs and twist them at brace height trying to gauge their "stability"..It has nothing what so ever to do with anything considering 90% of the power stroke the string is off the limbs. Lots of National and World championships have been won with twisted limbs. Just a lot of misguided opinions with no basis in fact....O.L.

You guys are getting into videos, here's a couple for you. There are others if you go to the root site..O.L.

http://talonoptix.com/HHvEdge2.html

http://talonoptix.com/HHvEdge1.html

Wow! Watch the limb twist and deformation in this one! :)....O.L.

http://talonoptix.com/Howard_Hill.html

If a bow is built using the same form with a different stack height and width taper to achieve the same # something WILL be different as far as the feel of the bow. maybe not to all guys but some really nit pick at the shooting characteristics of a bow. I think what Cedar may be refering to might be the extra vibration of some compared to others (possibly termed lack of vertical stability).I would think that any loss of side stability in a limb will also lead to lost performance because of the extra movement being wasted and energy not put into the arrow, right? In reference to speed when comparing the hypothetical above bows there WILL be a difference.(I know this because Ive built them both ways) Does any of this mean that one bow is "more" accurate than another. eh? I would have to say thats up to the guy behind the bow mostly. the bow dosnt win any accuracy contest without a good driver. and if one paticular brand of bow is out there more than another....well..., there again its a % game. Im finding out more and more that a bow doesnt have to have some BIG name or Big company and $$$$$$ backing it in the field to be "better". Hype sells too along with quality and performance. There are some really really good bows being built out of small shops and garages these days with both performance and shootability in mind and I believe that some of those bows would be winning shoots,& flight contests, if they were in the hands of more shooters. In the end it seems good marketing and money usually win.

Ken

I would hope not, with the wt.# of the L/B's he was shootin ...

Ken, "I would think that any loss of side stability in a limb will also lead to lost performance because of the extra movement being wasted and energy not put into the arrow, right?"

Let's assume for half a second that's correct. Then the highest performing bows would have the least of it. Right? From what I've seen bows like Olympic recurves have the most side to side stability and the most limb distortion during the shot yet they are some of the highest performing or at least preceived so. So either that theory is incorrect or the best bows would be greatly better then they already are. Can't be both. After watching that one video I may have to change my mind on what bow type wobbles around the most during the shot! :)....O.L.

OL, have you ever seen high speed film of your bows limbs when released? Wandering what they look like as well as others. I have not seen any, only the ones posted here. If they are out there can people post a link to them? Thanks Flint

Flint, No..Not sure what it would tell us? Logic would dictate an "unstable" bow would be untuneable and or not group well. If instability causes a shooter with crappy form to shoot poorly, well....If a bow is very forgiving to the point it covers up mistakes, a persons going to suffer there too. Shooting a cross bow isn't going to help us improve. Like I said earlier harping on stability and accuracy are attempts to change the subject from objective to subjective when there's a lot more imperical data showing it's moot point and more dependant on the archer then it is the equipment.

One thing I know for sure, the arrow only knows how hard it's pushed for how long period. Get the f/d curve as fat as possible without losing efficiency gets us there. There's a million shades of gray on the "how" to do that part.....O.L.

OL,you said

"From what I've seen bows like Olympic recurves have the most side to side stability and the most limb distortion during the shot yet they are some of the highest performing or at least preceived so" Wouldnt the excess limb "distortion"(Im assuming you mean on the shot) of an olympic recurve possibly be attributed to its overall length? I mean, they are very long limbed bows giving more room for wobble. I understand what you mean from the loose term "instability" being a moot point as far as accuracy goes, but soely from a performance standpoint and in all my experiments of testing thru a machine, bows that have a limb that occilates more after the shot dont seem to be as fast. Now mind you, Im not talking about recurves to longbows either, two totally different lengths and overall masses to compare those two equally.Just D/R to D/R bows mostly. I agree with you totally that getting the force draw curve as fat as possible is the best way to get the stored energy and potential for speed up but dont you think that excess limb movement IS "lost. efficiency"? To a degree this has to be true even if its a small degree. At the peak of bow performance 1fps here .5 there will add up.

I don't think vibration after the shot is any reflection on stability at all. It is simply the limbs way of getting rid of unused energy. When you pull the limbs back and then le them back down they go back at pretty much the same shape as when you pulled them and have almost exactlythe same pressure on the string both ways. When you release the string and allow this to happen fast is when things change. A very high energy storing recurve might be very fast and very stable but wind up at about 75% efficiency. After the arrow has left the bow this other 25% of energy has to be dissapated. I think a high speed camera would clearlyshow that bows approaching 90% efficiency don't vibrate much after the shot or distort much before the arrow leaves the string. This is where I believe the extra light outer limbs give the longbow a double bonus for low mass, I think they not only accelerate faster but also decelerate just enough at the end of the stroke for the mid limb to pull them through. They simply have less momentum in them when traveling fast to do their own thing and are much more compliant to the forces of the bow which are asking them to slow down so the string doesn't go slack before the shot is finished. I think high speed photography could prove or disprove this pretty easily. I found a guy near my house that will do an all day session for 350.00. If I can get some good test bows together I think I will have it done. Steve

Cedar, "But it is stability and accuracy that counts more than anything else. If you have a bow thats 10 fps faster and the limbs don't flop around after the shot and it is a Mild R/D design.."

I agree with you 100%, except the "mild R/D" part. I'm not out to make a "longbow", I like "good" bows. Could care less what they look like. Can't see the limbs when you shoot anyway! :) Besides subjective opinion, I'd sure like to know how to measure "stability"? :)....

Ken, To measure something you have to be able to isolate all other varables. So how would you measure that? Drawing conclusions after changing 47 variables as often as not leads us astray. Yep, I'd bet in similar bows and one flops around more then the one where most flopping around after the shot would perform less. Bet you dollars to donuts it stores less energy and or has less brace height tension also which are related. It would be a tough one to prove one way or the other.

Someday I'd like to do some high speed video work but it'll be from the left/right twisting as the string rolls off your fingers, off center. I suspect longbow configurations has less but even this I think is more influenced by the grip shape and how we grip. Really saw that playing with these useless "flight" bows. Can't bare shaft tune them so was shooting through paper and I could intentionally make the arrow "kick" any direction I wanted by slight changes in bow hand pressure. Was a real eye opener.....O.L.

OL, I believe your right that the word "stability" is difficult to measure, I guess what others and myself are refering to is the "visual" measurement one can get just by watching a bow fired out of a machine or side view when another person shoots it. Does this mean much?? well... YES. to some anyway. Its being brought up by more and more builders all the time.

As far as isolating "other" variables to measure one thing (didnt quite understand what you are refering to) but I think you have to consider everything as a whole and how it works together with the other variables. It is afterall 1 whole bow at a time we shoot, right?

I and many others like "good" bows too. and I also could care less what they look like. but good is also a relative term and can be a matter of opinion. All bows can be good, just some are "better" than others. (better in speed)(better in quietness) (better feel)(better quality).......

Since you brought up flight bows and I know your an expert in this field. do you ever use this as a method of bow performance testing? Or do variables like wind and perfect angle requirements, arrows,.. make this to difficult? I have often wondered if I should do some testing this way. But I know nothing about this branch of archery and also setting up "the right" arrows for doing this. Shure is fun though aiming high and letting em rip!!

Ken

"I don't think vibration after the shot is any reflection on stability at all. It is simply the limbs way of getting rid of unused energy."

I would completely disagree with this. Handshock (the initial thump) is a result of displaced energy, but repetitive flopping (as vibration can only occur with FREQUENCY...which means REPETITIVE bump, flop, bump, flop, etc.

So, perhaps we need to define stability. Stability = consistency. Forgiveness can be measured via consistency. The remaining energy is what is in the bow at brace. Any flopping around in my opinion purely shows instability...be it in the bowstring (as is seen with dacron) stretching back and forth (an instable behavior of inconsistant flopping)...and can be greatly eliminated with better strings like dynaflight.

Flopping around is typically a result of BOTH an instable bow and a stretchy string that exaggerates the problem.

That is why I would LOVE to see the video with a HH bow and a dynaflight/ff type string. I am certain the lack of vibration would greatly reduced even though handshock maybe present.

A HH type bow may be one of the least efficient, but it is very stable. Fortunately, you don't have to have a HH type bow to have a stable bow. One can have a stable bow even in a r/d design. Heck, I have one that I can bareshaft 20 yards. To do that a bow needs to be forgiving and stable...= consistent even when your not.

Lee, Maybe so, "but repetitive flopping (as vibration can only occur with FREQUENCY...which means REPETITIVE bump, flop, bump, flop, etc"

This all is the result of momentum/wasted energy AFTER the arrow is gone. Watch the videos again and watch the Hill's limbs during the power stroke. None of the other bows distort that much....O.L.

Lee and Cedar,

Very good points and well said by both. given the choice between two bows of equal performance but one has the excess "bump, flop", well.......Im taking the "good" bow.

Lee, I would agree that energy going into the limbs and being disapated there can contibute to handshock, thats where it comes from. The bows in the video above to my knowledge are all very low in handshock. All bows have some degree of flip flopping around after the shot. I think the science of grabbing that last little bit of flip flop is a worthwhie project to pursue. Hill bows are low on the list of efficiency from the ones I have seen. Also they get a lot of complaints regarding handshock, granted they are loved by many and that includes some world class shooters. Kenr's bow, to my knowledge has had the least amount of vibration I have ever witnessed and also the highest efficiency. Ken admittedly still needs to prove out his bows durability and repeatability but to my knowledge so far everything has gone well. I personaly think the design of the real speedsters may need to be backed off just a tad for public use but not by very much. Nice to think that a guy can draw 26" and get the speed most are getting at 28" or be able to shoot a 45# bow on any north american animal with confidence. This is what performance is really about, not just chaseing speed but using our brain to make something more efficient. You can take an old branch off a tree and if it will bend enough for a 28" draw you can get 150 fps out of it just by very minimal shaping. You can take wood and put it between two pieces of fiberglass shape it like a bow and it will likley hit over 170 fps. Guys who are trying to get a bit more out of a bow are not speed freaks, they are just men who like to use their brain a bit for a better archery experience. Steve

I just enjoy the challenge, never met a bow I didn't like! Glad to see someone brought up the string stretch hurting performance myth! :)....O.L.

OL, which video are you talking about. All the videos I saw with the HH bow being shot in slow motion were using dacron. The amount of flopping would be significantly less with dynaflight on that bow...just as the flopping around was CONSIDERABLE on the 21st with dacron.

The initial "thump" of handshock would be a result of wasted energy, but a dynaflight string takes that impact and stops. A dacron string stretches upon reaching brace and allows the bow to "recoil" so to speak and "store energy" in the string by loading the string...then this energy is released from the string and goes back to the bow...again the cycle repeats itself until finally the energy has discipated and reached equalibrum...into the archer or wherever. All this occurs with both dynaflight and dacron to some degree, but the problem of "vibration" continues to a much greater extent with dacron because dacron stretches (elastic, I am not talking about creep) much more than does dynaflight. There is no doubt that dyanflight/ff out perform dacron as well...but I wasn't even referring to the performance...I was referring to the stability.

Lee, I agree with all that. It was this one: http://talonoptix.com/Howard_Hill.html

Doesn't say what string was on it but I wasn't talking about the shake at the end, the limb deformation during the shot, the string won't cause that. Just never seen it so pronounced before?.....O.L.

Its amazing that with each bowyer here that there are some things I agree with and some that I do not. I do like a stable limb, I like very little vibration because it is basically lost energy which could be put into an arrow and I intensely dislike distortion during the shot as that has to effect the amount of energy put into the arrow and it has to effect the arrow flight. I have seen this proven over an over in vidios when I was target shooting. As to what Pokenhope said about the fita bows I would say that if they are flopping around like that then if they did not flop they would be even more accurate than they are. I do find that my personal experience coincides with that which Cedarsmith, Ken and Badger are saying. May we all strive to build a better product. It is the little things that count. I am in complete agreement with that,. a fps here and a fps there and suddenly you have a bow that was 180 shooting 190 and then 200 and then 205.

The force draw curve that I see as perfect begins at a high draw weitht at brace and pulls exactly 2 1/2 lb to 3 lb per inch out to the draw length then stacks at the next inch. Out that with very stiff , light weight materials , good bow design overall, perfecly timed limbs and balance and you will have a bow that performs well in all aspects. A fast bow does not have to be a bad performance bow. In fact vibration ect is just lost energy and that bow would perform better if it were designed properly.

Maybe I am wrong here but it sure seems to me that common sense is more important in good bow building than rocket science.

One last comment, I am thrilled to read OLs posts and Sids posts, along with Kens Steves ect. I respect you gentlemen greatly and am hanging on every word. In my limited experience I would say that three of the top speed bow builders in the world are posting on this forum right now. there is some good info going out here.

Limb Flop and stability.

When we destruct test limbs and bows they go into a large crossbow type jig and are repetitiveley dryfired the string is hand drawn to a crossbow latch and then triggered. One of the good things about a manual test is you get a chance to observe what is happening and so the conclusion is that if you draw the exact part of the string back into the latch and release there is no real vibration virtually zero. The limbs stop dead no real vibration. If you pull the string off one way or another even a little, vibration becomes apparent and the more it is off from the ideal location the greater the vibration untill limb flop occurs. The balance of a bow is how the bowyer sets it up. How well the archer addapts to the bow is another. Any well made bow will flop around if the archer's technique is off. If he does not push through the sweet spot then he has failed to load the limbs equally and vibration will occur and on extreemly bad technique limb flop is very apparent. And so the major culprit is the archer and his push technique and its position on the grip.

This will affect target bows more than others and not just because of length but also due to the mass of the riser and stabilizers. The off centred loads as just described are left to the limbs and not evened out so quickly as riser system mass prevents the bow from movinig as much. Less noticable on short bows due to length and the fact that the limbs and riser are more reactive together as the riser mass is much lower.

Stability in the lateral plane if the arrow launch angle varies 0.02" over the brace height distance at launch then at 20 yards you are almost 2" off and at 100 yards over 7" off. You have all seen much worse than this resulting from a plucked release. This is where limb stability comes in. This type of movement controle will not be seen on a slowmo video but it is very real. (again refer to the limb tests referred to earlier in this thread to archery Interchange (one of my posts) between three different makes of target limbs. The limbs ability to resist the sideways foreces imaparted into every shot that starts paradox. If the limbs are sensitive they will move laterally realativeley easily and exagerate the lateral path of the arrow nock changing the launch angle with every release variation. If shot consistently this is not a problem (an expert archer) but small variations in realese efficiency will be punished. A limb that is torsionally stiff will resist these side forces and hold the arrows in a narrower path improving consistency. As said earlier and perhaps not clear, the most stable of all limbs is a longbow limb that has a continuous curve from fadeout to nock.

The greater the reflex or recurve the more the limb will react to sideways forces and the less consistent the bow will perform for most people. A really good shot with excellent form can make this bow really perform especially in a tournament where he is working warm and repetitiveley (a hunter does not get this environment to make his shot (listening to Howard Hill once again):)).

We started stiffening our recurves with XP10 carbon an idea we introduced some 10 years ago and similar concepts are now being used by the big companies introduced only in their most recent products.

A target bow with all its external stabilisers makes the most use of torsionally stiffened limbs as the external stabilisers hold the riser in line allowing these stiff limbs to really resist these side loads. At one time we even discussed a formula 1 limb for expert target archers where we converted this massive reserve of stability into more speed (yes it is possibe to go even faster than we get today with the same stability that is normally seen on hunting bows). However the sponsorship programs of the big companies blocks us from the very top levels and so not our market. (I have been told that Hoyt spend approx $600,000 on their sponsorship program)Big company and very deep pockets. The marketing maxim and already refered to in this thread already, "the greater the marketing spend the greater the sales and not necissarly the best product"!

And so in our current range we simply continued with greater storred energy (HEX High energy Express) lower mass laminates and doubled the torsional stiffness. Our HEX5 for example appart from flight limbs has the greatest cord ratio that we have ever put into a hunting and tournament limb. The stability will match most advance longbow types and surpasses the HEX4 (tested 4 years ago)in smoothness and speed by a goodly margin.

You can see some of this public debate on Archery-Interchange http://www.archery-interchange.com/forum/border-archery/16695-our-limbs-there-construction.html

and

http://www.archery-interchange.com/forum/border-archery/12295-our-problems.html

Whether you shoot a longbow or recurve I think is not really performance dirven but asthetical even romantically driven. In many tournaments over here where recurves and longbows are restricted to Wood arrows the scores of the very top archers are similar; one year a longbow shooter has the highest score and on another its the recurver. However looking at the top ten places the Top ten recurvers have the same score levels as the top five longbowers. The recurve with it's silky performance grip position and bow mass proves more accurate than the longbow for many, many archers not all though. There is not a lot in it and bear in mind that the modern longbow well made with carbon lams will shoot alongside most recurves for speed and technically a more stable limb. Our own Griffon and Harrier bows will shoot as well as our XP30 recurves

You guys are lucky you can go hunting any time within season I have to travel as hunting here with the bow is illegal. The extra performance from the Recurve (hitting power) and more importantly the very compact size makes the recurve a doddle to carry in a standard suitcase :) However the longbow does almost as well but has a more woodsy feel a greater romantic inclination And now thanks to OL and Black Swan you don't have to have your teeth rattle out when you shoot a longbow. One thing though the more you move the design away from the longbow concept reflexed or three part TD or massive risers etc the more you move away from the fundamental reason for shooting one IMHO.

I have difficulty in understanding short longbows. Your own native tribes moved from longbows as would have been seen in Europe to short horse bows that in the end almost became recurved. These design changes came about over a very short period of time. If the developemnt had been allowed to continue most certainly they would have developed bows similar to the Trurkish bows, Sythian bows Mongle and tartar bows all recurved. It is the only way to keep a short bow smooth. If this is not the case and many would argue against what I have just said then why are all of the "short" longbow now showing significant reflex when braced. The very first step towards recurving a bow! That reflex does make the bow more sensitive less resistant to paradox forces :) It also stoes more energy in a design not suited to that when over short. it is smooth and defends speed.

Light blue touch paper an retire!!!! Sorry but remember we are longbow maker and make more longbows than hunting recurves. Most of the top shots in Europe shoot our longbows.

Great debate and a privalege to swap thoughts with you all and Ol in particular (don't know the rest you you other than we have the same passion bows and archery)

Sid

Oh yeah, Sid,

..and your bows look fabulous!!! (just checked your website)and our D/R bows look almost as though they come from the same form.

Dont stop now guys, keep it up , very good informative post. Thanks

Very good wrap up Sid and right on the money. It's that human interface that's tough. A bow with a 2x4 riser will shoot over and over in the same hole off a machine but no one could do so by hand.

Cedar, I have nothing against the bow you love and I'm not trying to replace them. Now if I could make recurves obsolete that's another matter! :) I didn't grow up with longbows but I did with recurves. The first longbow I ever shot I was not impressed. Any bow that requires me to hold it just so so, with this finger twisted around this way, but not if it's a Thursday is NOT a forgiving bow. I've heard the same over and over from folks wanting to get into traditional (conventional?) bows, if their first experience is with Hill style bows odds are they'll go to recurves. I have respect for those that can shoot them well but not for narrow mindedness! :)....O.L.

Sid says: the most stable of longbow limbs is one that has a continuous curve from the fade to the tip. Ken agrees, Steve agrees. Pic of my Eagle Wing

Six, is that the same bow we were shooting at the event? That bow was a screamer!! About the finest shooting bow I have ever shot. Steve

Sid,

I was happy to see your posts here. I love my Black Douglas.

My shoulders hurt a little but I exercise to keep them in shape. Very curious that you did not hear much about shoulders before and you do now. Maybe we've become a bunch of cissys or maybe we shoot heavier bows than they used to because so many of us came over from wheelie bows and feel like we just have to have a heavy draw. My bow is probably heavier than I need but I feel like my release is cleaner and my shoulders more in line with the heavier bow.

Thanks to everyone for all the info.

Steve, No I didn't send one this year. I hope to next year. That was probably Kens. It shot 201 at 10 gpi. that is as fast as a bow gets or right there. I believe his design is similar if I remember correctly but with a little less reflex.

ACS that was recently chrono'd. Good speed IMO

http://www.tradrag.com/forum/viewtopic.php?f=3&t=78

My comment about continuous curve refered to "when braced".

10 gpi and 201fps now that is some speed! One of the problem I have with speed statements is there is never a base to them.

Earlier I was under the mistake that a set of limbs AMO at 197 fps but OL says (author of the test) that that was at 28" at 30" it lifted to 205 fps a jumb of 8 fps.

10 gpi is one thing and you will get one speed at 28" another at 29" and so a draw length needs to be known also for that to actually mean something?

Looks a real good looking bow and I would be surprised if it did not show a bit of reflex when braced by the taper in the limbs. hard to really see mind you from the picture.

Can we see that braced at say 7" brace height???

Sid

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