Custom Bullet Upscale?

Discussion in 'Low Power Rocketry (LPR)' started by Back_at_it, Nov 18, 2019.

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  1. Nov 18, 2019 #1

    Back_at_it

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    Finally flew my Custom Bullet #10015 for the first time this weekend. Built it 15 yrs ago and never flew it until yesterday. Flew it on a B6-4 then a C6-3 using an 18 to 24mm adapter. After two successful flights, I'm thinking I want an upscale version. Thinking of building something to fly on a 29mm.

    My thoughts are to do a BT70 main tube with a BT60 inner and BT50's for the out board tubes. Has anyone done an upscale Bullet that wants to share?
     
  2. Nov 21, 2019 #2

    MALBAR 70

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    I've never done an upscale, but a BT70 based Bullet would be cool. Go for it!
    This thread reminded me that I have one in the build pile. I dug it out this morning and will start on it tonight.
    I like Custom Rockets kits, some of them would make excellent upscales. I have always wanted to do a BT70 based Ion Pulsar...someday...
     
  3. Nov 21, 2019 #3

    cwbullet

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    Do you have a rock sim?
     
  4. Nov 21, 2019 #4

    neil_w

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    Wait, what would be the function of the BT60 inner?
     
  5. Nov 21, 2019 #5

    MALBAR 70

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    Under the side pods, the main BT is necked down to a smaller size, then back up to it's original size.



    [​IMG]

    Photo courtesy of Rocket Reviews
     
  6. Nov 22, 2019 #6

    neil_w

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    Ah, didn’t notice that.

    Nice looking rocket, should work great as an upscale.
     
  7. Nov 22, 2019 #7

    Back_at_it

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    I don't have open rocket but i have done the math by hand. The upscale to BT70 will use a 1.67 multiplier.

    Upper tube will be 30.0"L.
    Lower tube will be 10.0"L.
    The gap with the exposed BT60 will be 1.67"L.
    BT50 side tubes will be 4.60"L.

    Over all the upscale should come in just a touch over 50 inches. Planning on building with a 29mm mount. Should fly nicely on an E16-4.
    Planning to do a Baffle and separate it somewhere in the center to avoid having to do a stuffer tube.

    Need to find a suitable nose cone. Been looking on ERockets and have a couple of options. Really wish there were more plastic options for BT70's. I'm probably the only person in the world that doesn't like balsa nose cones.
     
    Last edited: Nov 22, 2019
  8. Nov 22, 2019 #8

    Back_at_it

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    Do a build thread on the bullet.
     
  9. Nov 22, 2019 #9

    MALBAR 70

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    I'll consider it. I never did end up working on it last night, life (and toilet repairs got in the way). I will get to it this weekend. It's on the bench at least.
     

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