COAL vs OAL

Discussion in 'Reloading' started by Steve7mm08, Apr 30, 2009.

  1. Steve7mm08

    Steve7mm08 Well-Known Member

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    Oct 21, 2006
    This is most likely a stupid question, but nevertheless one that has been bugging me.

    What is the difference between COAL and OAL??

    If I use a stoney point comparator on my calipers does that give COAL or OAL?

    Someone put me right please

    Cheers, Steve
     
  2. woods

    woods Well-Known Member

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    Jun 4, 2006
    I consider COAL and OAL the same thing and is defined on the SAAMI Glossary

    SAAMI | Product Manuals

    in the 2nd definition

    "LENGTH, OVERALL
    1. Firearm: The dimension measured parallel to the axis of the bore from the muzzle to a line at right angles to the axis and tangent to the rearmost point of the butt-plate or grip.
    2. Ammunition: The greatest dimension of a loaded cartridge, i.e., from face of the head to the tip of the bullet for centerfire or rimfire or to the crimp for shotshells or blanks (not to be confused with the uncrimped length in a shotshell.) "

    You are not measuring the COAL or the OAL with the comparator. You are measuring to the point on the ogive that is close to caliber dimension. That is shorter than COAL but much more useful.
     

  3. Forester

    Forester Well-Known Member

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    436
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    Mar 23, 2008
    On a related note, is there a standard term for the measurement to the ogive? In my notes I just use OGL... I don't even record the actual OAL