Whisker Biscuit and Arrow Velocity

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This topic contains 71 replies, has 44 contributors, and was last updated by gjarcher gjarcher 6 months, 3 weeks ago.

Viewing 15 posts - 1 through 15 (of 72 total)
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  • February 16, 2007 at 4:13 pm #495411 Back to Top REPORT



    Joined: 5/24/2004
    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. [=}=]

    February 16, 2007 at 4:22 pm #509783 Back to Top REPORT
    vince71969
    vince71969


    Joined: 7/5/2004
    View My Bows
    You guys have the coolest toys :thumbup
    February 16, 2007 at 5:18 pm #509784 Back to Top REPORT
    tropicalfruitmom
    Tropicalfruitmom

    Joined: 8/6/2004
    You guys have the coolest toys :thumbup

    I want to come play in your toyshop!

    Thanks for the info. Yet another reason not to use a WB. :D

    February 16, 2007 at 5:29 pm #509785 Back to Top REPORT
    indychris
    Indychris

    Joined: 6/22/2004
    :thumbup

    Awesome test, Gators! Thanks for helping to keep us on top of all things archery!

    February 16, 2007 at 11:50 pm #509786 Back to Top REPORT
    iowaswitchback
    IowaSwitchback

    Joined: 11/26/2005
    Location: Guess!

    You guys have the coolest toys :thumbup

    I want to come play in your toyshop!

    Thanks for the info. Yet another reason not to use a WB. :D[/quote:2pc7dphd]

    With only losing that much speed How could you not use it? [=}=]

    February 17, 2007 at 1:41 am #509787 Back to Top REPORT
    symo
    Symo


    Joined: 6/29/2004
    The real intent of this post was so you could make an informed decision about whether you want to use one or not, not to imply that you should or should not use one. Some may see the amount of reduction as too much, while others may think that the loss is nothing compared to the benefits gained. We’ve already seen these two views in the responses so far. :thumbup
    February 17, 2007 at 1:50 am #509788 Back to Top REPORT



    Joined: 5/24/2004
    very intersting results . i would have thought there would been a greater loss of speed from friction. thanks for posting that jon :thumbup
    February 17, 2007 at 3:33 am #509789 Back to Top REPORT
    jeff-k-in-il
    Jeff K in IL

    Age: 26
    Joined: 11/1/2005
    Wow, I need to spend time with Jon, he will teach me all I need to know… :shock:

    Interesting report as well.. :thumbup

    February 17, 2007 at 3:39 am #509790 Back to Top REPORT
    thunderchicken21
    thunderchicken21

    Age: 30
    Joined: 8/4/2006
    Location: Ohio
    Very interesting 8D Thanks for the great report [=}=]
    All We Do Is SELFILMED
    February 18, 2007 at 4:27 am #509791 Back to Top REPORT
    ironmaiden
    IRONMAIDEN

    Joined: 9/27/2005
    very interesting! thanks :thumbup i have to wonder though if there was no fletch contact at all , like duck29’s trimmed WB..i’ll cut one up and send it to ya? :whistle :whistle :^O :^O

    February 18, 2007 at 4:59 pm #509792 Back to Top REPORT
    tbolden
    tbolden

    Joined: 1/31/2005
    Thanks for the info. You guys make it well worth the time spent here. Plus the fact that you just tell it like it is and let everyone make there own decisions. =D/>” title=”Applause” />  <img src=
    February 19, 2007 at 6:20 am #509793 Back to Top REPORT
    chiller
    Chiller

    Joined: 11/13/2006
    Great info!
    February 19, 2007 at 6:58 am #509794 Back to Top REPORT
    kill-em-all
    KILL EM ALL

    Joined: 1/18/2006
    thanks for the info
    I want to come over and play 2 :D :^O :^O
    February 19, 2007 at 10:15 am #509795 Back to Top REPORT
    bowtie1201
    bowtie1201

    Joined: 7/16/2005
    great info…thought it would take more speed away than that…. :thumbup :thumbup
    February 19, 2007 at 10:07 pm #509796 Back to Top REPORT



    Joined: 5/24/2004
    One factor you may have left out is also bow torque. My wife was shooting the WB and I noticed she was grabbing the bow right at the shot and she would get erratic arrow flight. I took off the WB and installed a drop away rest and her groups tightened up immediately. She also picked up about 5 fps. I know there is no substitution for good form but I’d still like to have the most forgiving set up I can get my hands on.
Viewing 15 posts - 1 through 15 (of 72 total)