tac speed

Discussion in 'PSE TAC 15/15i Crossbow Hunting Forum' started by J calvin, Oct 3, 2011.

  1. J calvin

    J calvin Member

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    Sep 22, 2011
    Ha guys i used my friends small stabilizer chronograph to find what speed i was shooting,it read 370fs from my tac 15i why is it shooting so slow or that type of chronograph reads wrong or could it be the limb savers i have in the limbs.It is only my 8th shot with this new tac 15i.
     
  2. jon.henry755

    jon.henry755 Well-Known Member

    Messages:
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    Dec 16, 2010
    Hi J calvin,
    How much weight are using on arrows? Are these standard 85 grain points or something else?

    What type of a chronograph are you using and at what distance from the end of the crossbow are you shooting?

    Please give everybody enough specific information to be able to assess the possibilities.

    Regards,

    Jon
     

  3. OkieBowie

    OkieBowie Well-Known Member

    Messages:
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    Aug 28, 2010
    As jon.henry755 stated make sure you are using PSE's factory default 85-grain points. After that...

    I would try measuring the arrow speed using another chronograph. If possible, one specifically meant to use with high-speed arrows or slow moving projectiles. Some chronographs are designed to not register objects below pistol / rifle velocities. Also some chronographs will reject or give bad readings when both the light-change sensors are both showing an object passing through at the same time. (aka long arrow vs. short bullet). One brand rejects any reading where the starting sensor is not triggered first.

    If you are still seeing slow speeds there is a possibility that your TAC-15i's strings do not have the correct amount of twists in them to set the cams and limbs to their maximum energy areas.
    My advice is to get a PSE TAC-15 expert to help you add the twists. It is not a simple process, in that you are not adding twists to the entire bow string. Instead you are adding twists to the "Y"'s loop ends that attach to the Cams' bearing shafts, and you can easily inadvertently torque the cams to where they lean.
     
  4. jon.henry755

    jon.henry755 Well-Known Member

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    Dec 16, 2010
    Hi J Calvin,
    Please take heed to what OkieBowie is telling you in his message and provide him your feedback. You've got the attention of some of the brightest people anywhere when it comes to these crossbows and they are sharing some of the best advice you'll ever get on the likely source of your problem.

    At least let him know what the problem turns out to be or what you learn from his advice. These threads are interactive so others can also learn by reading them.

    Okie,
    Thanks for the sound advice and information. There was some information in your write up that I knew nothing about, since I've always used a chrono that was designed specifically for archery.

    Jon