confused with 22 barrel to round tolerances

Discussion in 'Gunsmithing Forum' started by Uncle_McPeanut, Jan 20, 2011.

  1. Uncle_McPeanut

    Uncle_McPeanut New Member

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    hi ive done a bit of research and found that the round is slightly larger than the crest of the twist and is size for size or a tiny size smaller that the valley
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  2. c3shooter

    c3shooter Administrator Staff Member

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    Not sure exactly what you are asking (too long on an airplane today and I am a bit punchy)- however, IN GENERAL- bullets fit themselves to the bore when fired (within limits) Process is sometimes called obturation- the softer metal is squeezed to fit snugly, and be gripped by the rifling. otherwise propellant gasses would blow past the bullet.
     
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  3. skullcrusher

    skullcrusher New Member

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    Little confused here as well, and I have not been up in Seward's Folly.

    C3 is correct as usual. The diameter of the bullet is a tad larger than the diameter of the rifling on a barrel. That way, the rifiling can grip the softer bullet and spin the bullet to stablize it during flight. The groove diameter is nearly equal to the bullet diameter so gasses won't just blow by the bullet.
     
  4. Uncle_McPeanut

    Uncle_McPeanut New Member

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    cool thank you thats the answer i wanted
    ive worked in the engineering trade for a bit and learned about tolerances and it just seemed a bit weird that the bullet was bigger than the id of the bore but makes sense because of its explosive power
     
  5. Uncle_McPeanut

    Uncle_McPeanut New Member

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    how have you made 9700 posts and you joined later the c3 how often do you go on this sight?