How to index a brake?

Discussion in 'General Rifle Discussion' started by NF50AR, Jul 22, 2013.

  1. NF50AR

    NF50AR New Member

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    Just as the title reads... I want to know if anyone can explain the process of indexing/timing a brake for a large caliber rifle?
     
    Last edited by a moderator: Jul 23, 2013
  2. SSGN_Doc

    SSGN_Doc Well-Known Member

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    Usually with a crush or a peel washer. You may need to know the torque specs, but you are probably pretty safe between 16 and 20 ft/lbs. a peel washer has layers that you can peel of to get to the right thickness so that your muzzle device is indexed at the right torque range. With a crush washer you torque to your max torque, then back it off, then re-torque, and back it off repeatedly until it is indexed and in the appropriate torque range.
     

  3. NF50AR

    NF50AR New Member

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    Okay, so I guess it is that simple. I was thinking there was more to it when you get into big calibers.
     
  4. JonM

    JonM Moderator

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    If your going to mount a suppressor on a qd brake or flash suppressor dont use a crush washer ever.
     
  5. bildee

    bildee New Member

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    any particular reason for that comment about crush washers and cans?
     
  6. Grizzdude

    Grizzdude New Member

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    I'd like to know this too?
     
  7. hoovco

    hoovco New Member

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    I have a bit written up here ... Lemme find it. Get your calculator out.
     
  8. hoovco

    hoovco New Member

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    A threaded barrel with a thread pitch of 5/8 - 24 has a 5/8" inch threaded diameter and 24 threads per inch of threaded barrel.

    Every 360 degree turn of a device advances the device 1/24th of an inch.

    1/24 = 0.04166666666 inch

    0.04166666666/ 360 = 0.00011574074

    Every degree turned advances the device 0.00011574074 inch

    So if my device, torqued down to spec is advanced 45 degrees ahead of being timed, I would have to create a shim that is 0.00520833333 inch.
     
  9. hoovco

    hoovco New Member

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    Your variables in this equation are the thread pitch, and the degrees ahead of timing.
     
  10. hoovco

    hoovco New Member

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    You don't have to be super exact with the degrees, +/- a little bit of torque won't hurt anything.
     
  11. NF50AR

    NF50AR New Member

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    A threaded barrel with a thread pitch of 5/8 - 24 has a 5/8" inch threaded diameter and 24 threads per inch of threaded barrel.

    Every 360 degree turn of a device advances the device 1/24th of an inch.

    1/24 = 0.04166666666 inch

    0.04166666666/ 360 = 0.00011574074

    Every degree turned advances the device 0.00011574074 inch

    So if my device, torqued down to spec is advanced 45 degrees ahead of being timed, I would have to create a shim that is 0.00520833333 inch.

    That's the exact answer I'm looking for! Thanks hoovco
     
    Last edited: Jul 25, 2013
  12. bildee

    bildee New Member

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    and if a crush washer is used, what's all of this mean to us?
     
  13. hoovco

    hoovco New Member

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    Just torque it down until it lines up. It's a crush washer. It flattens so you can index your device.
     
  14. hoovco

    hoovco New Member

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    A shim is the best way to do it though. I only use crush washers on the old birdcage flash hiders.