Arrow weight used for speed tests

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Arrow weight used for speed tests

#1 Post by longbow steve » Fri Aug 10, 2007 11:24 am

Wondering if anyone knows the weight arrow that manufacturers use to determine speed specifications of their bows? Is there a standard weight?
Steve

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#2 Post by Stickbow Hunter » Fri Aug 10, 2007 11:36 am

I believe 540 grains to be the standard Steve.

It used to be with a 60# bow drawn to 30 inches but I think it may have been reduced to 28" for trad which makes more sense to me as not too many people draw trad bows to 30".

Search for the AMO standards as that may give you the full answer.

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#3 Post by longbow steve » Fri Aug 10, 2007 11:59 am

Thanks Jeff, I found a site that listed AMO standards and IBO standards,
You are correct a 60lb bow measured at 30" is the benchmark, using 540gr or 9 gr pp conversion to the bow tested.
IBO is a set 5gr pp their example was a 70lb bow should use a 350 gr arrow for test purposes. Almost a dryfire IMO

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#4 Post by Stickbow Hunter » Fri Aug 10, 2007 1:17 pm

Steve,

I had a suspicion that there was some Trad standards committe now that may have changed the draw to 28" but I'm not certain. I haven't kept up with the latest.

Over the years a mate and I have spent many hours carefully testing many bows and it can be interesting. Haven't done much in recent times though.

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#5 Post by LBR » Sat Aug 18, 2007 12:00 am

There is an AMO (or whatever it's called now--the name changed some time ago) standard, but as far as I know there is no organization that caters strictly to traditional bows or regulates any testing.

Tests can be skewed in a number of ways, so I'm leery of them. They can be changed purposely, or by someone who just doesn't understand all the variables involved. Arrow weight is just one small part of the equation.

I'm no engineer, and I don't do any "official" testing, but even I know that the following can change the outcome:

arrow spine
string material
number of strands in the string
length and size (weight) of serving (if any at all)
nock fit
AMO draw length vs. "true draw" length (1.75" difference)
chronograph calibration, light source, sky screens, etc.
glove vs. tab vs. shooting machine
distance of chronograph from the bow being shot

I'm sure there's more--that's just the one's I can think of. I've seen a few claims of 200+ fps AMO, but I've never seen it in person--at least not from a trad bow. I've only read a very few reports, and these were not done in what I consider "real world" conditions--with the same set-up that would be used for hunting, or even target shooting. 'Course a shooting machine is the only way to eliminate variables that come with a finger release, but nobody will get the same speed using fingers as the shooting machine gets, and some designs will be more sensitive to release errors.

Botom line, I generally take speed test reports with a grain of salt unless I personally know the person doing the testing, know they are honest, and know they are able to conduct a fair test.

Chad
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#6 Post by longbow steve » Sat Aug 18, 2007 6:53 am

Hi Chad, thanks for your input. I agree about the variables that come into play when using the chrono as we struck some when testing in the garage.
This is the first time we have used Arthurs new chrono so we did the usual boy thing of pulling it out of the box shooting through it, wondering why it wasnt working, then tossing a coin to see who would have to read the instructions :lol:
The line I read said to shoot from a minimum of one arrow length away, with plenty of light. This made me wonder whether an arrow has reached full velocity at this stage, I suppose if the spine is stiff enough and the arrow is no longer paradoxing maybe?
Our tests were done on my new recurve with 2317 arrows fitted with 125gr points, I guesstimate they were approximately 650gr so was happy when they passed through at 185fps with my 26 draw length, light 550gr arrows went well over the 200fps mark which prompted my initial post as I had heard/read somewhere that 350-380 gr arrows were the standard.
It is all good fun, by no means is speed everything but when coupled with an ultra stable bow I think Its a winner. :) Steve

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#7 Post by GrahameA » Sat Aug 18, 2007 7:23 am

Hi Chad

I am very much in favour of numbers done under a standard set of conditions. (It's the Techo' in me.) As with all things tests done under laboratory conditions they are done that way as they are repeatable and you can control the environment. Experience suggests that the performance in the real world may significantly vary from that done in the lab - unless the lab conditions replicate the real world. :D

The current standard used for calculating IBO speed imakes for interesting read. :shock:
http://www.archeryexchange.com/informat ... -ibo.shtml

Steve

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After that all it is going to do is slow down.
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#8 Post by Jeffro » Sat Aug 18, 2007 8:16 am

Steve, what is your new recurve and what are the specs?
I recently put about 40 arrows through a chrono and found them to get an average of 177FPS.The highest I got was 181
That was with a 3 peice Bob Lee bow which are regarded as being up there amongst some of the quickest .I was using a 23\64 shaft and have no idea what they weigh.The bow is 62#@28.
A friend of mine Heath put arrows through the same chrono at the time using a 65# 1 peice recurve made by some bloke in QLD(not huntsman)Its a short bow probably 56" with bamboo limbs and I could visibly see that it shot them out quicker than mine as we were doing the course of 3D targets before using the chrono.
He was averaging about 185FPS with some being 191 and lower.
When I hear mention of speeds over 200FPS it makes me wonder .
A check mate bow I recently sold was claimed by its previous owner that it shot 192 FPS .It was 56#@28".I shot the bow in my back yard and it was not as hard hitting as my bow nor was it visibly as fast.
As chad said I have not seen a recurve do these speeds or heard from someone I trust that one has.I just dont think it happens unless the bow is about a 75 pounder using light weight carbons or something.
You say your arrows were 550 grain doing over 200 FPS from a recurve ?
I dont believe it mate,not meaning to sound funny but if what your saying is true it must be one hell of a recurve and i'd love to see it in action at the gathering.

Jeff

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#9 Post by LBR » Sun Aug 19, 2007 10:13 am

I figure that a real test would be too much of a pain for anyone to bother with, and I also figure there would be some bowyers/manufacturers crying foul when "real world" tests showed speeds much lower than published reports. One thing I'd want to see would be silencers added and a decimeter used to measure the noise--add enough silencers so all would have the same noise level. Even that opens up another way to fudge on the numbers--a smaller amount of silencer material in the right spot will do as much or more good than a lot of silencer material in the wrong spot.

Chronographs can vary quite a bit, from one to the next. They can also vary depending on light conditions, distance, etc. etc. etc. One fellow may get much better or much worse numbers than someone else with the same bow--not to mention difference in draw length and release, which throws arrow spine back into the equation.

A feller can't trust his eyes either--our brains won't pick up 10-15 fps difference, and from what I've seen that is generally the spread in the better performing bows (when all else is equal). Improperly tuned arrows won't fly as well or as fast, a wobbly arrow flying just as fast will appear slower and have less impact, etc. Other things can play tricks on our eyes as well.

For example, I saw a fellow shooting clean through backstop netting with a bow pulling less than 50#, while that same netting stopped arrows shot from bows around 70#. Did that mean the 40-something pound bow shot harder than the 65-70# bows? Not hardly! The lighter bow was immaculately tuned, carbon arrows were used, and they had very sharp and pointed tips. The heavier draw weight was shooting wood arrows with much larger diameter and duller points.

There was a lot of "ooohs" and "ahhhhs" when the light bow sent an arrow through the netting, and lots of comments made about how it was shooting harder than the heavier bows. It was a very fast bow, but it wasn't putting more energy behind those light carbons than the heavy bow was putting into the heavy wood arrows, nor were they impacting harder--although it looked that way. I've seen similar cases when carbon arrows sunk deeper into foam targets--looks can be decieving.

Speed tests will measure performance, if the bows are set up equally well, but then you still have noise, forgiveness, hand shock, stability, etc. etc. etc.

It seems like more and more folks are falling into the speed trap, and it's becoming more and more of a selling point. I really hate to see that happen. Not that a fast bow is a bad thing, but I don't think the emphasis should be on speed alone.

Chad
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Robertson

#10 Post by kimall » Sun Aug 19, 2007 6:03 pm

I have a Robertson Falcon 63# at 28 and it will shoot between 195-199 all day long with a carbon arrow four fletch 580 grain.I did some fairly extensive testing with differant arrows,strings and tab and glove in a post some time ago if I can dig it up I will repost.
Cheers KIM

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Found it

#11 Post by kimall » Sun Aug 19, 2007 6:15 pm

Ok found the thread guys here is what I found.
I was lucky enough today to get a chrono for a day or so and was able to test my trad bows through it with some interesting results.It is very hard to guess how fast a bow is just by shooting it and this is a real bull@#$% stopper when it comes to talking about how fast a bow is.
I tried a couple of differant set ups on the Robertson and the Defiant so here are the results.I weighted both bows on the scale first and at my drw lenght of about 27 1/2-28 they both pulled around 61 pound so this made it easier to compare results with them being so close.I tried the Robertson (which is a recurve) with the string that came on it and one of my own I made this week and this string is made out off 8125 with 12 strands and the supplied is fastflight of about 16 strands both with woolies on them and both sound very quiet.The longbow has a 8125 string also but no other string and this helped it a bit in the test I believe.Arrows where the same carbons shot out of both bows in two differant weights.29 inchs with 4 four inch sheild cut feathers and 200 grain points with rubber up the hv ones.Arrow weights are 740 grains which is about 12.2 grains per pound and the lighter ones being only 480 grains which is only just under 8 grains per pound.I am not going to hunt with these lighter arrows as I feel they are a bit unstable in flight but it was an interesting weight to uses as a bottom weight for testing.I checked with the bow maker and he said it would not harm the bow in any way.
Recurve Supplied string
740grn-----164 feet per sec
480grn-----188 fps
Recurve Kimall String
740grn------172 fps
480grn------196fps :shock:
Longbow
740grn------150 fps
480grn------190 fps
These figs are the averages after at least 10 shots with each setup and it started to show a very clear picture.A couple of things the suprised me a bit was that my string was consistantly faster by enough to make a differance on arrow flight down range.The other thing that is often said is that longbows really shine with a extra heavey arrow and they do but as shown here they do REAL well with a lighter arrow as the weight of the arrow got less the speed diff was not as great between the two bows.The very fastest I got with the lighter arrow was from the curve at 199.5 fps.
and as much as I would like to say I cracked the 200 it was not to be and I may have to change the name of the bow to "ALMOST" or "199" :D
I have some heritage shafts coming in a softer spine so I should be able to make up some arrows about the middle of these and should give me about 180 fps with 10 grains per pound and these should be a nice hunting and field shooting balance.I hope this was of interest for some and thanks for reading.Any question just shoot.
Cheers KIM
PS MY release is not flash

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#12 Post by longbow steve » Sun Aug 19, 2007 7:31 pm

Wow. I had no idea what speed should be expected out of a trad bow as all I have to compare with is touted compound speeds exceeding 300fps and now talk of 400fps.
Jeffro you are correct, the bow is 70lbs so shooting 500 odd grains should come out at a rate of knots, carrying 9-10 grp/lb to over 180 odd fps is good and I am happy with the way it feels.
I will be at the Wisemans Ferry shoot should you still be dubious about the speeds, but having seen Kimalls test averages I dont think my recurve is out of the ordinary and recently Graeme K recorded speeds of 170 fps out of a 50 lb bow why then is the 200 fps mark so unacheivable or unbelievable.
Chad the reason I ordered on of these bows is the stability factor first, very much forward handle design, about mid range as far as lengths go and I can GUARANTEE anyone who shoots this bow will be impressed.
Looking forward to getting it and posting pics. Steve

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#13 Post by greybeard » Sun Aug 19, 2007 7:59 pm

Hi,
Thanks to all for the info on chronographs. After a mate brought one around to my place we played around for about half an hour. I do not know if it was properly calibrated but do know they won’t work successfully under fluorescent light so we used it in a bright area in the back yard. I decided to buy one as I could see the advantages as an aid in bow design and selection of materials used in building an efficient bow. Some customers want a bow for hunting, some for target. Hopefully the chronograph will form part of the base to build a more efficient bow. Grain scales and a custom made backstop (to measure penetration) will be added to the shopping list.
The results of our play in the backyard are as follows.
Bow; Reflexed longbow, Hickory core under 40 thou glass #50 @28” fast-flite string.
Arrows; 27½”, 4” feathers, 125 grn brass points.
Hardwood footed Quondong 560 grn arrows best speed 170 worst 163 f.p.s.
Hoop pine not footed 510 grn arrows best speed 182.4 worst 178 f.p.s.
Mediterranean release with leather tab.
I would not class the above tests as conclusive because the enviroment was not controlled.
I know speed is not everything but it must play a part in the equation of bow design.
When I get my own chrono set up I hope to get more accurate figures.
Daryl.
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#14 Post by Jeffro » Sun Aug 19, 2007 8:33 pm

I am going on the sunday steve so looking forward to checking it out.

What is the bow?

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#15 Post by LBR » Sun Aug 19, 2007 11:42 pm

why then is the 200 fps mark so unacheivable or unbelievable
It can be acheived, even blown out of the water--with the right set-up. I have no doubt I could get speeds in excess of 220 fps with my longbow, but that would be with light arrows, tiny string, no silencers, short serving, long draw, etc. A friend of mine was able to get as much as 232 fps with his longbow shooting light arrows--and that was with a hunting string and silencers, drawing 29". Based on that, with my 30.5" draw and fudging in other areas I should be able to get in the 240's--but I'd never think about hunting with that set-up, and the bow wouldn't last long being shot with such light arrows.

Try 10 grains per lb, drawn to 28", with a normal hunting string, finger release, etc. and it won't happen, or at least I haven't seen it happen and have seen no verified reports of it happening. That seems to be the "Holy Grail" of traditional bows, so it seems that if anyone were to acheive it honestly it would be known and verified quickly. I have seen some claims, but as I said...........

Didn't mean to pick on you Steve--didn't realize you have a bow on order, don't know what bow it is--just giving my opinions. Over the years I've seen so much advertising spin I've become a skeptic, and with my own business I'm used to the first question being "how fast is it?". A legitamate question, but still given way too much emphasis IMO.

Again, nothing wrong with a fast bow--I like fast bows, and shoot a fast longbow (although I very much enjoy shooting my selfbow also, and it's comparably slow). I just get tired of advertising hype, and will try to put it into perspective. Most of our new archers don't realize that todays traditional bows shoot arrows as fast or faster than compounds from not too many years ago, and that practically every big game animal on earth has been taken with bows we'd consider to be average at best these days.

One of the Wensel brothers said it best (I can never remember if it was Gene or Barry): "That deer doesn't care how fast your arrow is going when it flies over his back!".

Chad
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#16 Post by longbow steve » Mon Aug 20, 2007 7:25 am

Hi Jeffro/Chad/Darryl, I claimed 180 fps with hunting weight arrows, a string I just made with 17 strands, full length serving, no fudging of the figures there. The light arrows which were my longbow arrows although reaching the 200 mark sounded horrible coming out of the bow and would not be considered by me when going into the field after game. The reason I ordered a bow of this weight is out of respect for the game I may pursue, namely big pigs.
I also put one of my d shaped longbows through its paces, carrying 10gr/lb and it gave a modest 150 fps, this is also the gear I use for tournaments and feel the speed is adequate and probably good enough for all of our light game species.
Darryl, I know your bows are quite fast, as I said in a post recently I had the pleasure of shooting one of your D/R spotted gum bows and it gave nothing away to its American counterparts, I also feel that you already have the design down pat and all that could be benificial would maybe a lighter core material??? I found the Chrono may be useful as a form guide, if you are able to maintain the same speed coming out you are releasing consistently. Steve

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#17 Post by Jeffro » Mon Aug 20, 2007 8:06 am

So is it a secret then :?

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#18 Post by longbow steve » Mon Aug 20, 2007 8:10 am

Sorry Jeffro, The bow is made by Arthur fisk at Bathurst, a known American design that he purchased plans for. Steve

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#19 Post by GrahameA » Mon Aug 20, 2007 8:25 am

The 200 fps Holy Grail. My understanding about it is this.

For selfbows - it is a challenge to reach it. The materials become the limiting factor.

*****************

imho - Speed is not everything but does fit in with the American psyche. Thus the difference in design philosophies of American automakers and European automakers. Which is exemplified by the culture that makes Drag Racing popular in the US but not in Europe.
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#20 Post by Jeffro » Mon Aug 20, 2007 9:42 am

Thanks Steve,I hope to see you next sunday at Roberts if your gonna be there.

Jeff

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#21 Post by Dennis La Varenne » Tue Aug 21, 2007 10:42 pm

To all,

I suppose I regard myself as a bit of a techo like Grahame. Everybody knows (I thought) that 'real world' bow performance will always be different for all the reasons that LBR listed.

However, the point of manufacturers claims and their own standardized testing is to remove as much of human error as possible so that bow and arrow combination can be compared with like equipment under controlled conditions.

All it allows one to say is that where all else is equal, an archer could expect to get X% greater or less arrow speed or arrow penetration than another bow/arrow combination. It is then up to we archers to make informed judgements about which equipment combination is more likely to meet our requirements.

Nobody in their common sense mind would expect the laboratory claims to be matchable with human usage . . . would they?

Any standardized testing is always valuable since it informs any intending purchaser to make judgements about equipment choices. It is similar to the testing of rifle/ammo combinations from a benchrest where as much human error as possible is removed from the testing so that one can see the potential of the equipment itself.

Inferring that lab testing has no place or is misleading is to completely miss the point of the exercise. By the same token, an archer with excellent shooting form will get more from an average bow than an archer using a rated high performance bow with poor shooting form.

Surely no-one would buy or dismiss 'x' brand of bow based upon how it shot under real-world conditions used by an archer of unquantifiable skill on a bad or good day?

Dennis La Varenne
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#22 Post by LBR » Wed Aug 22, 2007 2:09 am

Dennis, my point was/is that many of the tests I've read were misleading. Maybe not intentionally, but I'm not alone in that respect. Often you have to get into the "fine print" to learn that a test was done on a shooting machine, with release aid, etc. Also, many factors are often left out or buried in the fine print--specifics on the string, arrow, draw length, etc.

Those not familiar with how the testing is done are going to expect similar results when they shoot, and are going to be very dissapointed when they don't get it. When I was getting into the sport, I had no idea there was a such thing as a shooting machine--I believed what I read/heard, and expected to be able to get the same results with the bow in my hand. 'Course that was long before speed became such a selling point with traditional bows. When I got a chronograph several years ago I began to get enlightened. I learned that what many folks were calling 200 fps was usually 165-175 fps. I also learned that most were just parroting what they had heard about their bows, and hadn't even shot through a chronograph--back to my original point above.

Again, there are too many variables that will let the test numbers be slanted one way or another, puposely or not. I haven't witnessed any formal testing, but have read a report or three and talked with a fellow that witnessed a test. Without going into detail, I learned enough to make me leery. As far as I know, there is no "standardized" test--the methods used are up to the person doing the testing. I've heard and read several conflicting reports--so who's do you believe?

Another problem is speed is just one part of the equation. A shooting machine won't measure a bow's forgiveness, hand shock, noise, etc. Speed is one thing that can be measured comparably easily, but it gets way too much emphasis IMO.

I don't mean to imply there's a bunch of dishonest people doing tests--that's not my point at all. Speed tests just don't mean that much when you put them in perspective. As Ken Beck once told me, "there's not a nickle's worth of difference in the performance of the better bows on the market today."

Personally, if I'm at a point where I'd have to look to see who's bow is 5-10 fps faster to decide on which bow to hunt with, I'm going to hunt something smaller or just shoot targets with my bow. If I'm that close to not having enough bow for the job, I hope I'm ethical enough to give it up or at least use a different weapon.

Back to the original topic though--as far as I know there is no standard for everyone to follow, and no orgainization to enforce it if there were--at least with traditional bows. Until then, speed tests are interesting to read but not something I'll put a lot of faith in.

Chad
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#23 Post by Dennis La Varenne » Wed Aug 22, 2007 4:16 pm

Chad,

I thought my comments before yours supported yours actually.

I know as well as anyone that the 'tested' specs of any bow rarely match what the user gets from it. That is what I said. I also said that would anyone be so lacking in common sense as to seriously consider that they would obtain that advertised performance.

I then went on to say that if bows were tested by machine (or any other reproducible technique) it would allow one bow to be compared with another to see what any given bow was capable of under ideal conditions.

Idiosyncratic things such as forgiving', smoothness, etc. vary from archer to archer and can never be measured. I for one cannot feel smoothness of draw or have ever been able to. If I contradict someone who avows that it exists, how is it that two persons cannot agree. This is something which any manufacturer cannot or would not lay claim to in their specs, because it cannot be measured and so cannot be objective.

Whether or not the archery industry has a coherent standardized testing regime (it probably should have) I do not know for a fact. I thought that they did through the Archery Manufacturers' Organization of the US - one of the principal archery manufacturers in the world.

Whether they exist or not is another matter. There is a universal longstanding informal standard in the trad field that arrow speed is measured from a 28 inch draw and bow length measured from the bow nock to bow nock along the back surface of the bow. Speed is usually taken by chronograph at one arrow length from the electrodes.

Anyway, as you say, if this is done 'by hand', the only claim can be made by the shooter that 'X' speed was what was able to be got from a test using 'Y' equipment during testing. The important thing is that the technique is systematically and logically set out and logged so that others can use the same technique to validate a result or not.

Anyway, I/we are hijacking the thread a bit.

Dennis La Varenne
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#24 Post by GrahameA » Wed Aug 22, 2007 5:10 pm

Good Afternoon Chad and Dennis
Idiosyncratic things such as forgiving', smoothness, etc. vary from archer to archer and can never be measured. I for one cannot feel smoothness of draw or have ever been able to. If I contradict someone who avows that it exists, how is it that two persons cannot agree. This is something which any manufacturer cannot or would not lay claim to in their specs, because it cannot be measured and so cannot be objective.
I have a simplistic view on some things. One is if you cannot measure something it does not exist. What that usually ends up meaning that to measure something requires a bit more sophistication than what is available plus a definiton of what term means.

For me things such as "forgiveness" in a bow is an opinion. Nothing wrong with that but just remember it is an opinion. What one person consider to be forgiving is not necessarilly the same as what somebody else considers it to be. For me "Smoothness" is all about the force draw curve - it should a smooth with no sudden change of rate.

I could talk about this stuff for ages but suffice to say I am very wary of manufacturers comments unless they are accompanied by the numbers and their testing method. Plus to compare one manufacturers numbers with anothers when they are not obtained using the same method is like comparing apples to oranges. And that is not just with regard to bows - it includes all manufactured items.

It would be interesting to get some real numbers on bows. e.g. What is the mean time to failure for a set of limbs when drawn to there rated deflection? And how is this changed if they are over drawn?? (How times can you draw the bow before you can it to expect it to fail?)

How about bow efficiences or the forces generated when the limbs are stopped by the string? Need a few accelarometers here.

Personally I am of the opinion that companies do not like to publish such information as it starts to show just how different or not so different some things actually are. :D
Grahame.
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LBR
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#25 Post by LBR » Thu Aug 23, 2007 5:31 am

I think we both misunderstood some Dennis--I may still be misunderstanding.
I also said that would anyone be so lacking in common sense as to seriously consider that they would obtain that advertised performance.
My answer to this is a definate "YES!". Some folks don't realize how tests are done, they just read advertisements, catalogs, and/or message boards about how fast this or that bow is. Lots more don't have acess to computers, some don't read message boards, etc.
I then went on to say that if bows were tested by machine (or any other reproducible technique) it would allow one bow to be compared with another to see what any given bow was capable of under ideal conditions.
I agree, it would be a fair comparison in that one area, as long as all was done equally. Things such as arrow spine, nock fit, number of strands in the string, length and size of serving, how the string is made, how much wax, etc. etc. etc. can all make a difference though, and can pollute the results.
Idiosyncratic things such as forgiving', smoothness, etc. vary from archer to archer and can never be measured.
Well, they can and they cannot. Smoothness can be measured on a scale (draw force curve), but how smooth a bow feels to the archer can vary. Pre-load will affect how smooth a bow feels to me.

I'm sure a machine could be built to measure forgiveness as well, if anyone had a notion to do so. It could torque the string a certain amount, torque the bow a certain amount, drop the "bow arm" at release, etc. and see how much accuracy suffered from one to the next. We know that a shelf cut past center will be more forgiving of arrow spine. We know a deflexed riser is more forgiving that a straight or reflexed riser--'course figureing out how much difference it makes could be a bugger to put on paper.

The AMO isn't a manufacturer, but an organization that manufacturer's can join. Since 2003 it's been known as the ATA, or Archery Trade Association. I really don't know how one goes about getting ATA certification on a test report, but I also haven't seen any reports on traditional bows that claimed to be ATA certified.

Whether they exist or not is another matter. There is a universal longstanding informal standard in the trad field that arrow speed is measured from a 28 inch draw and bow length measured from the bow nock to bow nock along the back surface of the bow. Speed is usually taken by chronograph at one arrow length from the electrodes.
That's the kicker--it's informal. AMO (ATA) states that draw length is measured from the deepest part of the grip, plus 1.75 inches. This is usually the back of the shelf, or very close, but it will vary. Also, you have "true draw" thrown into the mix. I've seen tests where this was used--as best I can tell, it's measured from the deepest part of the grip, period--basically adding 1.75" to the actual draw length. For instance, a test using a 28" "true draw" standard would be about the same as a 29.75" draw by AMO standards.

For me things such as "forgiveness" in a bow is an opinion. Nothing wrong with that but just remember it is an opinion.
Well, yes and no. Although I can't tell you how to measure a bow's forgiveness, it is not just an opinion. We know that things such as a deflexed riser, shelf cut to or past center, higher brace height, etc. add forgiveness to a set-up. On the other hand, opinions will vary on whether a bow is forgiving or not. For instance, if you have a problem with torque a bow with a reflexed riser is not going to be as forgiving for you as a bow with a deflexed riser. If someone doesn't have any problem with torque, the deflexed riser won't be any more forgiving.
I am very wary of manufacturers comments unless they are accompanied by the numbers and their testing method. Plus to compare one manufacturers numbers with anothers when they are not obtained using the same method is like comparing apples to oranges
I agree--I'm wary period, because I don't feel I know enough about it to know just what all to look for.
Personally I am of the opinion that companies do not like to publish such information as it starts to show just how different or not so different some things actually are.
I'd bet that is the case with many. Other reasons could be smaller operations just don't have the time or money to invest in verified testing, and I know of one that just doesn't care what the reports say. They don't advertise at all, but rather let their products sell themselves via happy customer's comments.

Interesting stuff!

Chad
Long Bows Rule!

Dennis La Varenne
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#26 Post by Dennis La Varenne » Thu Aug 23, 2007 7:23 pm

Chad,

No problems here. I/we could quibble over a few things like 'forgiveness' etc. but essentially we are on the same wavelength I think - just different approaches.

Regards,

Dennis La Varenne
Dennis La Varénne

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