Arrow Speed for Accuracy - info source needed.

[Joester]

Hi all,
I'm in the final throws of designing a Chronograph for my final year Uni project.

In the technical report, I am discussing the requirement for needing a chronograph in the first place.
It is obvious (factors such as wind and manufacturing tolerances notwithstanding) that a faster arrow flies straighter for longer and hence is more accurate than a heavier arrow.

I need to reference a few quotes to this effect, but I am having trouble finding a reputable source of this sort of information on-line.

Please can anyone:

a) provide a URL to a decent site I can quote from (e.g. manufacturer's site).
b) type out a few lines from any tuning books you might have that reinforce the above (including title, author, page no. and year).

Much Obliged.

Joe

P.S
Please can we not have an arguement about how true the above statement is !
I'm fully aware there are many more factors at work than just speed.

[greydog]

Originally Posted by Joester

It is obvious (factors such as wind and manufacturing tolerances notwithstanding) that a faster arrow flies straighter for longer and hence is more accurate than a heavier arrow.

Hmmmm, good luck defending that statement

Other reasons for a chronograph are to help tune your bow, putting speed nocks on your string (see the other thread) strand count, amount of serving, comparing different string materials for speed and consistancy, optomising cam rotation, tuning brace height, nock tightness, fletching size, point weight variation.......you can get feedback for all these things from your arrow speed

[Joester]

yep yep,
I know, and I have had no trouble finding quotable sources to back-up issues of tuning.
Its purely the speed = accuracy thing.

It can't be a complete misnomer can it ? - especially indoors.

[bowcoach]

You might have a look at Coach Kisik Lee's website:

http://www.kslinternationalarchery.c...rrowSpeed.html

Here he talks about the impact of arrow speed on scores for elite level archery.

Good Luck,

-Daniel

[pHz]

just thinking out loud

the speed = accuracy thing might hold a little water

but only if everything else on the bow and with the archer is optimal - a fast arrow shot out of an inaccurate setup will be just as inaccurate as a slower arrow - itll just be inaccurate faster

also in theory more speed = flatter trajectory = less time in the air = less affected by wind etc but that (a) is again only true if everything else is optimal and (b) slower arrows can be compensated for by adjustments to equipment etc

slainte : rob

[Joester]

Originally Posted by bowcoach

You might have a look at Coach Kisik Lee's website:

http://www.kslinternationalarchery.c...rrowSpeed.html

Here he talks about the impact of arrow speed on scores for elite level archery.

Good Luck,

-Daniel

Perfect !
Many Thanks !

J

[greydog]

Yes, in theory a faster arrow is in the air for less time and so is less affected by weather, a heavier arrow being slower and exposed for longer. The heavier arrow is able to resist the effects of wind/rain better than a light arrow, so it comes down to there being an optimal balance between speed and weight......the arrow that is in the air for the shortest time, but has the best mass to resist outside forces. This is probably one of the reasons heavy point weights are popular, letting you shoot a mid weight shaft for speed, but loading the nose up for extra momentum.

Without seeing any real data on the issue there would seem to be too many variables to prove a lighter shaft is more accurate than a heavier one, it certainly doesn't hold true indoors, where a very broad range of shaft weights are used succesfully.

If wind is taken out of the mix, then a light weight arrow, giving a flatter trajectory could prove more accurate out to a certain distance, as the low mass will cause it to parachute dramatically after that. This is why for unmarked field (or 3D in the States) some people prefer a very light shaft as they will go to 60M before their trajectory starts to deteriorate, giving very tight sight marks making distance estimation less critical.

[joetapley]

Originally Posted by Joester

Hi all,
I'm in the final throws of designing a Chronograph for my final year Uni project.

In the technical report, I am discussing the requirement for needing a chronograph in the first place.
It is obvious (factors such as wind and manufacturing tolerances notwithstanding) that a faster arrow flies straighter for longer and hence is more accurate than a heavier arrow.

I need to reference a few quotes to this effect, but I am having trouble finding a reputable source of this sort of information on-line.

Please can anyone:

a) provide a URL to a decent site I can quote from (e.g. manufacturer's site).
b) type out a few lines from any tuning books you might have that reinforce the above (including title, author, page no. and year).

Much Obliged.

Joe

P.S
Please can we not have an arguement about how true the above statement is !
I'm fully aware there are many more factors at work than just speed.

Can't help at all with speed v accuracy references but if you haven't read it the following should be of some interest. http://www.bio.vu.nl/thb/users/kooi/tuko92.pdf ( European Journal of Physics, 13:127-134.

[JohnKR]

a faster arrow flies straighter for longer and hence is more accurate than a heavier arrow.

I know you said lets not argue about the accuracy of the statement but it appears you are using two properties (speed & weight) as interchangeable. A faster arrow does not have to be a lighter arrow, although a heavier arrow would admittedly need more energy to propel it (to the same speed) than a lighter one. I would think a heavier arrow, at the same speed as a light one, would be less prone to wind effects. A more pertinent question would be, if shot from the same bow, would it be better to shoot a faster, lighter arrow, or a heavier, slower arrow?

I think the LiSik Lee article is considering the importance of consistency, as opposed to any benefits from increased arrow speed.

Perhaps the benefit gained from a chronograph is to asses the best combinations of weight and speed.

John.

[bowcoach]

I think Lee’s article suggests how reducing an archer’s average time per shot can influence arrow speeds, and in doing so he illustrates how arrow speeds are important.

Speed is an important factor at this level; otherwise male archers would really have no incentive to shoot bows above 50 pounds. They could just as easily shoot 40-42 pounds as women generally do.

Further, I think it is more the profile of the arrow that is of importance than the weight. If you shoot a light arrow that has a large profile, it will not produce optimum groups at the farther distances of 70m and 90m, due to it being more susceptible to drag and other forces. A heavier arrow with a low profile can group well, hence the X10 shaft.

Obviously, there are advantages to having a light high profile arrow, where it can take up a little more space on a target, thus theoretically speaking giving the archer a slight advantage such as in 3D archery.

Indoor archery is relatively the same principle; many want the larger shafts (line breakers). Still while others prefer to focus on the most forgiving set-up.

At long distances accuracy becomes the most important variable for shaft selection. So far accuracy has been achieved by developing a balance between weight and profile, so that the effects of drag and wind are minimal and downrange speed is optimized.