Adjustments to load after adding muzzle brake

Discussion in 'Reloading' started by carpetman2, Sep 16, 2013.

  1. carpetman2

    carpetman2 Well-Known Member

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    I just added a muzzle brake and have several loads developed over the past 4 years. Is there an average rule to re-dial my loads, such as it will most likely use less powder or more powder? And seating depth should not change , right? Just looking to cut to the chase if I can.
     
  2. jkupper

    jkupper Well-Known Member

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    When I added a brake to my gun it didn't change anything. The load that I had previously developed was still tight, and the point of impact did not change. I do not know if this is the norm though.
     

  3. trebark

    trebark Well-Known Member

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    Generally speaking if you add a brake to a custom barrel (not a factory barrel) you should see only a minor shift in point-of-impact if any.
     
  4. CB11WYO

    CB11WYO Well-Known Member

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    +1

    Might try a few groups to see though...
     
  5. jkupper

    jkupper Well-Known Member

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    Mine was a factory barrel :D
     
  6. westcliffe01

    westcliffe01 Well-Known Member

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    A muzzle break is an added mass on the end of the barrel, so it will change the vibrational properties of the barrel for sure. Whether that has any substantial impact depends on whether it causes a shift in the timing of the shock wave that travels through the barrel at the point the bullet is leaving the muzzle and you probably have a 50/50 chance that it will.

    If the POI shifts, all you should have to do is find your new powder charge accuracy node which may be higher or lower than it was before. There should be no reason to change your seating depth since the MB does not change the throat...
     
  7. carpetman2

    carpetman2 Well-Known Member

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    Mine is on a factory barrel and your correct, the new accuracy node seems to be .4 grains less. We shall see if I can continue to duplicate. Thanks for the info.