How to make + shoot the bullpup crossbow

Discussion in 'The latest one!' started by JoergS, Sep 18, 2011.

  1. JoergS

    JoergS Administrator

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    <embed pluginspage="http://www.macromedia.com/go/getflashplayer" src="http://www.youtube.com/v/JGEovOb4GQ4" width="425" height="350" type="application/x-shockwave-flash" wmode="transparent" quality="high" scale="exactfit"></embed>
     
  2. McMilchreis

    McMilchreis New Member

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    How long are the bands you use on the bullpup? I like the design, it reminds me of the P90 assault rifle. Can you use smaller steelballs with it?
     

  3. JoergS

    JoergS Administrator

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    The bands are cut 25 cm long, but only 16 cm are effective bandlength. This means that they are stretched 500% roughly, very close to the max. <br><br>I can use smaller balls in theory, but not with this pouch (it has a large center hole). <br><br>The center hole in the pouch is absolutely necessary, otherwise the ball may slip out of the pouch when you shoot.
     
  4. Antraxx

    Antraxx #7

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    That one came out veeeery nice.<br>Good design, powerful and precise i bet.<br><br>Good job!
     
  5. LifelongHabit

    LifelongHabit New Member

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    I love this. Without a doubt your best design yet, the trigger mechanism in particular is elegant in it's simplicity.<br><br>Have you calculated the energy yet? It looks like it would be suitable as a hunting weapon.
     
  6. DukaThe

    DukaThe New Member

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    Thanks for that tutorial Joerg. Realy great rifle <img src="http://illiweb.com/fa/i/smiles/icon_smile.gif" alt="Smile" longdesc="2">
     
  7. McMilchreis

    McMilchreis New Member

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    Mh thanks Jörg for reply. I think i will try to build my own one and style it like i like it. Maybe i will try a smaller pouch and thera tubes for a longer lifetime.
     
  8. John S

    John S New Member

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    It looks just like an AUG very nicely done!
     
  9. Nebuchadnezzar

    Nebuchadnezzar New Member

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    I was wondering how you handled the trigger to sear connection, para-cord is pretty ingenious.<br><br>You could even play with different "weight" triggers by adjusting the strength of your rubber band return.
     
  10. Antraxx

    Antraxx #7

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    i´m wondering if there is a small dynamagnet included in the triggermechanism, to prevent the bullet from rolling of while cocking. a simple carved curve would also do the job ofc.
     
  11. Nebuchadnezzar

    Nebuchadnezzar New Member

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    <table width="90%" cellspacing="1" cellpadding="0" border="0" align="center">
    <tr><td><span class="genmed"><b>Antraxx wrote:</b></span></td></tr>
    <tr><td class="quote">i´m wondering if there is a small dynamagnet included in the triggermechanism, to prevent the bullet from rolling of while cocking. a simple carved curve would also do the job ofc.</td></tr>
    </table>
    <span class="postbody"><br><br>The pressure from the bands holding the shot against the frame should be great enough to keep it from slipping out. To help load it it may not be a bad idea to drill a slot for a small rare earth magnet.</span>
     
  12. John S

    John S New Member

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    They do have those magnets in pinball machines
     
  13. Miniman

    Miniman New Member

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    going to make one of these
     
  14. ttabor

    ttabor New Member

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    Oh wow, what a cool slingshot!! Er..slinggun maybe? <img src="http://illiweb.com/fa/i/smiles/icon_smile.gif" alt="Smile" longdesc="2"> I bet it could be modified to shoot arrows as well. How accurate is the scope? Is it just there for coolness factor?
     
  15. JoergS

    JoergS Administrator

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    I planned to use a rare earth magnet, but couldn't find one, even though I should have had at least ten lying around... tidyness, where are you when you're needed? <img src="http://illiweb.com/fa/i/smiles/icon_smile.gif" alt="Smile" longdesc="2"><br><br>No big deal, it works pretty good without the magnet.<br><br>Scope is very accurate, certainly not just for the coolness. Iron sights would work OK, too - we are talking effective distances of maybe 30 yards or so. <br><br>I may do a variation of it that shoots bolts, but I prefer balls, cheaper and less vulnerable.
     
  16. Ryan Wigglesworth

    Ryan Wigglesworth Senior Member

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    Holy hannah 30 yards... :s That is a very long distance for pinpoint accuracy
     
  17. BavarianBarbarian

    BavarianBarbarian New Member

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    Hey guys! I've had some time to make a Sling-X-Bow and finished it yesterday. I shot it a minute ago and it is a lot of fun. But most of the time the ball hops out to the side instead of being shot straight forward. I'm not sure yet, what the problem is, but maybe you could help me if i post some photos of the mechanism.
     
  18. JoergS

    JoergS Administrator

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    Did you punch a large enough center hole into the pouch?<br><br>60% of the diameter of the balls you are using is ideal. So 12 mm hole for 20 mm balls, or 9 mm hole for 15 mm balls.
     
  19. BavarianBarbarian

    BavarianBarbarian New Member

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    Thanks for the hint, Jörg! The hole in my pouch is smaller, so I'll make it larger and try again. But this may take some time, because I decided to add a handle to the front of the gun, first.<br>I'll report on the topic as soon as possible!<br><br><i>Edit</i>: I now tested it with a larger hole and it worked great. Thanks again! The front handle is done, too, but I'll have to finish the junction to the frame tomorrow. Then I can go on testing and probably take some pictures.
     
  20. natalino

    natalino New Member

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    this design its ok but com be improve for more assault look