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Just a note on the W.B. If you have spent any time on this or any other forum in the last year or so you will be familiar with the popularity of the Whisker Bisket. The number of people that like or dis-like them seems to be fairly evenly divided. No doubt those that like the WB, like how easy it is to set up and how quickly they are able to get good arrow flight. Many like the full containment feature of the rest and the fact that they are not likely to have their arrow fall off from their rest at the moment of truth and they are willing to sacrifice some arrow launch velocity to have this feature. On the other hand the more experienced archers seem to gravitate toward rests that do not tend to reduce the launch velocity of their arrows when their bows are properly tuned. We recently did some testing designed to determine how much the WB affected Arrow launch velocity and found that there were a number of factors that had an influence on the arrows launch velocity when the WB was used. The WB tested had arrow entry in the 4th. quadrant and was composed of two different bristle colors. The bristles that supported the arrow on the sides and above were brown in color and measured about .008” in dia. The bristles that supported the bottom portion of the arrow were black in color and measured about .010” in diameter. The circular opening in the center of the WB measured .314” in diameter ( a .315” dia gage pin would not slide through the opening under its own weight.) The chronograph used to measure arrow velocities was capable of measuring the launch velocities of the arrows tested to less than 0.25 fps accuracy, verifiably. We shot a number of different diameter arrows and we shot arrows having different types of fletching. The idea was to determine what effect arrow shaft friction played in reducing the arrows launch velocity and also to what extent did the arrows fletching contribute to the loss in launch velocity. The bow that was used in the test was machine shot from exactly the same draw length for each shot and the nocking point travel was straight line in both the horizontal and vertical planes which should have minimized the force variations exerted on the O.D. of the shaft during launch. ( ie: the bow was well tuned) All of the fletched arrows that were shot were fletched straight offset and the fletching was oriented such that each of the three fletch passed thru the brown bristles. Conclusions: 1. When the arrow shaft diameter is only slightly larger than the W.B. opening, the velocity loss was 3fps of which a little over 1fps was due to shaft friction. 2. When the arrow shaft diameter is .015 to .020” less than the W.B. opening the velocity loss was about 2fps. With the 3” vanes showing slightly less loss than the 4” vanes. (less than .5fps) and the 5” feathers being in between the two. 3. The velocity loss is proportional to the degree that the arrow shaft is larger than the natural opening size of the W.B. There was a velocity loss if 4.6 fps when the shaft was about .085” larger, resulting in loss due to shaft friction being almost triple that of an arrow properly sized for the W.B. I have seen some posts on this forum where people have attributed as much as 5fps or more velocity loss to the W.B. and I can see from our testing that such values could be possible. Especially if one considers the possible combination of a larger diameter shaft, 5” helical fletched vanes and a poorly tuned bow or a bow having less than desirable nocking point travel. Just thought that I would pass this on for what ever it might be worth.
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