posted
What I am thinking is the energy stored on 3 bows are about the same providing they drew to the same length with the same weight. However those shorter bows have less total mass weight (arrow+limb+string) to move in the light arrow situation. Once shooting the heavier arrows, the effect from the less (limb+string) weight is no longer significant.
Posts: 468 | From: LI-New York | Registered: Nov 2009
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posted
Thanks all for the education, good stuff here as always.
-------------------- Currently intoxicated with the Emerald glow of the Northern Mist...... Posts: 1833 | From: New York - LI | Registered: Nov 2008
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posted
If the most efficient bow is faster regardless of weight, then why is there a 7 to 10 fps difference at the lower weight and the same speed at the higher weight. I know it is not a scientific study just a thought.
I know one bowyer I talked with said that if you wanted to shoot heavy arrows then use a heavier limb core like osage. If you plan on shooting light arrows then use a lighter core like bamboo. I don't know if this is accurate but I do know that mass moves mass.
-------------------- It's not the arrival, it's the journey. Posts: 1704 | From: Back in North GA FOREVER | Registered: Jul 2007
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posted
I don't think bad bows pass up good bows just by adding arrow weight. I think bad bows have farther to go, so they seem to improve more as arrow weight goes up.
-------------------- "Teach him horsemanship and archery, and teach him to despise all lies" -Herodotus Posts: 3468 | From: Linn, MO | Registered: Oct 2004
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posted
Matchchaser , great question but already answered in some of the posts. the heavier arrow uses the energy in the heavy limb more efficiently. thus as you go up in arrow weight the two bows get closer and closer to same speed. However the more efficient bow will still be the better performing bow. If only by a half ft per second. The less efficeint bow will never surpass the performance of the more efficient bow of the same poundage. No matter the conformation of the limb.
posted
Then that means there is not much difference between the performance of bows if you use heavy arrows. The speed bows only have a noticeable advantage with lighter arrows. I like heavy arrows so this is good. I do understand that the more efficient bow loses ground as arrow weight goes up but wouldn't this trend continue? If the less efficient bow made up 5 to 7 fps in a couple gpp then would it still be behind in a couple more gpp? Interesting. Please don't take this as an argument just a thought.
-------------------- It's not the arrival, it's the journey. Posts: 1704 | From: Back in North GA FOREVER | Registered: Jul 2007
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quote:Originally posted by JimB: I understand the longer limbs being more effecient but why are they less efficient with the lighter arrow?
I'm wondering if the longer limbed bow has a lower brace height than the other bows.That may help some with heavy arrows.
The brace height on my bows are all 7.25". Limb core on the Whip is bamboo, and on the fastest 58 incher is maple. I don't know enough about woods to tell if this is the difference. The limbs are a different width, the short bow mentioned above is about 3/8 of an inch wider. The Whip has very narrow limbs.
Good discussion folks, thx for the replies.
Posts: 150 | From: Saskatoon, Saskatchewan | Registered: Dec 2007
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posted
Lighter arrows will always extract less energy from the bow.
It's difficult to measure exactly what we get. Bows are like people, we might be built exactly alike, but our performance will vary. You'll find different performance in bows of equal weight, even when made by the same bowyer.
Posts: 747 | From: Wasilla, Alaska | Registered: Jan 2008
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posted
Matchchaser, I have tested hundreds of bows and never seen a bow that was less efficient outperform a more efficient bow no matter the arrow weight. If you have two bows of equal weight and one is more efficient it will always be more efficient even though the numbers come closer together the heavier the arrow. They might get close to even but the less efficient bow will never shoot the arrow faster except occasionally within the margin of error. You may get a few shots faster within the margin of error of the chrono but if you shot 100 arrows the more efficient bow would outperform the lesser bow.
An interesting thing is that the more efficient bow will also be the best mannered bow when shooting lighter arrows because it is transferring the energy into the arrow instead of losing the energy in the form of shock and vibration.
Its an old trick to hide a poorly designed bow by saying it is designed to shoot heavy arrows. Basically it is a smokescreen for a shocky bow.
posted
Sixby, in all your testing have you ever noticed any statistical difference in efficiency between different lenghts of longbows?
I've only tested my 3 bows so don't have the advantage of the amount of data you must have collected over the course of your testing.
Posts: 150 | From: Saskatoon, Saskatchewan | Registered: Dec 2007
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quote:Originally posted by HATCHCHASER: Then that means there is not much difference between the performance of bows if you use heavy arrows. The speed bows only have a noticeable advantage with lighter arrows. I like heavy arrows so this is good. I do understand that the more efficient bow loses ground as arrow weight goes up but wouldn't this trend continue? If the less efficient bow made up 5 to 7 fps in a couple gpp then would it still be behind in a couple more gpp? Interesting. Please don't take this as an argument just a thought.
The less efficient bow will never take over the more efficient bow.
Look at it this way. That heavy bow limb will remain a heavy bow limb and will sponge up just as much energy to get it moving no matter how heavy an arrow you put on it. You can realize some gains by making the arrow stay on the string longer, but the more efficient bow is also gaining.
-------------------- "Teach him horsemanship and archery, and teach him to despise all lies" -Herodotus Posts: 3468 | From: Linn, MO | Registered: Oct 2004
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posted
Well Said George. I have not noticed as much difference in efficiency in bow lengths as I have in bow design. Total design including riser ,. Stiffness ect. Some of the most efficient bows I have seen are 64 in D and R longbows.
A couple of bows tested at the WTT last year were in the hi 90s.
There is a lot of hype put out by some builders about this bow or that bow being the new Valhallah of all bows . That is usually until they are tested under controlled conditions and exact measurements . Some bows are the real deal though and I will give credit where credit is due. Centaur is the real deal. They were tested against some of the other highly touted bows and although the other bows performed well they were smoked by Centaur. Except for Whippinstick and Sasquatch. They were in that same high 190s class at 10 gpi . those bows were all unbelieveably efficient bows.
I'm not shilling for any of them and have no stake in them. Except for Kirk at Sasquatch I have not even met any of them. But they are what they are. Finely made efficient bows by master bowyers that understand bow dynamics and physics.
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