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Discussion Starter #1
Hi there,
Does anybody know if there is an average amount of speed lost per inch of drawlength lost from the IBO listings. I guess what I am asking is if a bow shoots 300 fps with a 30" draw, what would the same setup shoot whith a 26.5" draw?
Thanks
Bob
 

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See if someone on the board will put your bow info into their archery program. That will tell you exactly how much you will lose.
 

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From what I've heard, the rule of thumb it 10fps for every inch in draw length adjustment. So, 300 - 35 = 265fps. Just an estimation though.

Jeremy
 

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It's more complicated than a simple number but in my experience most modern bows lose around 15 f/s per inch of draw. This puts you around 240-245 f/s using this simple method.

Most bows as the draw gets shorter actually increase slightly in effeciency due to things like string weight, draw curve etc. With this in mind it would be best to calibrate The Archery Program to your bow with YOUR draw length. This way any changes made to your arrow and draw weight will be properly accounted for.

Hope this has helped.
 

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Discussion Starter #5
OUCH!:eek: 40-50 fps seems like alot of speed to loose. I've seen those little speed balls and whatnot to put on the bow string to get more speed. Do you guys think that stuff works, or is it just a gimick.
 

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Speed balls.............it's so funny you should ask!

Just last week a young man locally had installed speed balls on his bow and realized a 18 f/s increase! I didn't believe this could be true so he agreed to take them off and we would re-test the bow without and then again with them on. Well to make a long story short there was no speed increase worth mentioning.

We don't know for sure what happened the first time around with the Chrono.....but the second test shows that in this case the speed balls did nothing or very little.

In my own experience with them I never realized more than just a few feet, and that was achieved after hours of trials with moving them up and down the string to get to the sweet spot. Not worth it in my opinion. The claims of quietness is where they should spend there money......not the speed increase.
 

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JustShoot-

I too used to go by that method......around 10f/s per inch. The problem arrises in taking the limb's printed draw length as gospel. Order a 29" bow and then shoot it with an IBO arrow and low and behold you lose around 7-10 f/s! amazing, but now measure the draw length.......:( Most bows will be off by at least 1/4 inch, and many as much as 5/8 ich and more. Doing a quick math test you will see the calculated speed loss of around 15 f/s is very accurate and a much better rule of thumb.
 

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Discussion Starter #9
Ok, here I go again. I have narrowed the field to two bows. The Pearson Diamondback VX, and the Forge CW33. I have had the oppertunity to shoot both of these bows, and like both of them very much. I am leaning towards the Pearson because there is a locall dealer, where as the nearest Forge dealer is over 100 miles away, but according to both of the manufacters numbers the Forge is about 15 fps faster then the Pearson at my drawlength. Is 15 fps really all that much? I mean if I set up both bows and shot one right after the other would I really notice the difference in speed?
Thanks
Bob
 

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I would say that 15fps is a significant difference. Especially in your case of a short draw length. Are both the bows the same price? If you really like them both the same I would go with the faster bow. This is considering all other things equal though. However, if you're not prepared to work on your own bow I would strongly consider buying from the closer shop. 100 miles is a long way for a peep adjustment.

Jeremy
 
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