Curious about bullet fragmentation.

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by 7mm Eclipse, Nov 4, 2009.

  1. 7mm Eclipse

    7mm Eclipse Well-Known Member

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    Jan 19, 2009
    I have read that the lower weight bullets pushed at higher velocities with fast twist rate barrels can fragment before reaching the target.

    Are there specific designs of bullets that tend to be worst than others?

    Is this fragmentation also seen when the lower weight Barnes Triple Shock all copper bullets are shot under the same conditions?

    Thanks,

    Mike
     
  2. Locknload

    Locknload Active Member

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    Sep 21, 2009
    Mike,
    99% of the time the bullet disentegrates when the jacket comes off the bullet. The lead core can not hold together, without the jacket, and vaporizes with a grey puff of smoke. This can be done several ways, high rpm, thin jacket and a very high velocity or a defective jacket. I have also had jackets stop in the barrel and eject just the core. This can happen with an open base and large hollow point bullet.

    If you are shooting a Barnes solid copper bullet, it does not have a jacket to shed.

    However, with a high capacity cartridge, you can at times push a bullet at a high enough velocity to strip the bullet. This is when the bullet actually does not take the lands and goes straight down the barrel. A stripped bullet leaves a big mess in your barrel. Most stripping occours with cast bullets but can happen with jacketed bullets as well, at extreame velocity.
    Best,
    Ed
     

  3. elkaholic

    elkaholic Well-Known Member

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    Agree with locknload! Even the various types of lands can have an extra effect. i.e 3 groove with a small dia. bullet. I had some 180 v-max come unglued in my 300 ultra at about 3400 with an 11 twist.....Rich
     
  4. J E Custom

    J E Custom Well-Known Member

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    Jul 29, 2004
    Typically fast twist do this if the velocity is high or in the case of the big magnums if you use a
    lite bullet and push it to fast it will/may shed the jacket.

    Example = Take a 223 rem and place a 40gr bullet in it at max pressure and fast twist (1 in 7)
    and you wont have any problems, But take the same bullet and twist and chamber it in a
    223 WSSM and you will almost assuredly shed the jackets.

    Also big bores .375+ normally have a slower twist because of the starting shear of the big
    bullet is much higher than a lite one and they will tend to strip the jacket as Locknload said.

    The trend is to faster twist but that is for the heaver bullets in a caliber for stability and if
    you want velocity and lighter bullets you need to slow the twist down,

    This phenomenon is not to common unless a person pushes the envelope .

    J E CUSTOM