twistin'

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by rlipson, Jan 20, 2002.

  1. rlipson

    rlipson Well-Known Member

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    Dec 21, 2001
    twistin\'

    Question:

    Seems like the prevailing wisdom on twist rates is to not cut it too close, and go with a fast enough twist to guarantee stabalizing the heaviest possible bullet for a given caliber. So, what is the DOWN side of fast twist? Fouling? Wear? Bullet deformation?

    Roger
     
  2. Len Backus

    Len Backus Administrator Staff Member

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    Re: twistin\'

    Fouling and the potential for higher pressure and therefor lower velocity.
     
  3. Fergus Bailey

    Fergus Bailey Well-Known Member

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    May 3, 2001
    Re: twistin\'

    In pure accuracy terms, you want the twist that will be just on the “right” side of accuracy with the bullet you have chosen. You want to spin the bullet just enough for stability, but no more.

    It is not possible to “over stabilise” a bullet as such, but spinning a bullet faster that is needed is more likely to produce erratic behaviour if there is any defect in the bullet. There is always a degree of compromise in choosing a twist rate for a barrel as there are a number of variables that will affect bullet stability - but that is about a chapter long explanation that I am probably not ideally suited to giving.

    Fergus