Base to ogive 175 SMK

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Bishop, Mar 16, 2014.

  1. Bishop

    Bishop Well-Known Member

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    Just got done measuring the base to ogive of some 175 smk's. To be clear i am measuring the bullet alone, not a loaded round.

    The difference between the two lots (for the most common length i sorted to) was .005 +.

    My question is what have you guys observed in bergers for base of bullet to ogive length uniformity. How about lot to lot consistency?

    In the smk's of both lots i noticed a +\- .010 spread within lots on both lots. However the ES from the longest base to ogive from lot A to the shortest base to ogive for lot B was .020. So had i loaded from both lots I could have ended up shooting bullets that varied up to .020 in length from base of bullet to ogive.

    Just curious about anyone else's experience.
     
  2. Bishop

    Bishop Well-Known Member

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    Weeeell I guess I will buy some and see for myself.
     
  3. Mikecr

    Mikecr Well-Known Member

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    Thing is, base to ogive is meaningless.
    You have here:

    End diameter
    Base length
    Base angle
    Bearing diameter
    Bearing length
    Ogive datum to bearing

    The first rule in measurement is one thing at a time.
    With these individual numbers summed together(as you're taking them), you cannot know what is good or bad in your readings, or what any affect might be.

    You should stop and think it over a bit.
     
  4. Bishop

    Bishop Well-Known Member

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    So using a comparator and sorting my bullets doesnt help me any?
     
  5. Mikecr

    Mikecr Well-Known Member

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    That's correct.
    Your sorting could be the very worst thing to do.
     
  6. Bishop

    Bishop Well-Known Member

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    Good i didnt like doing it anyway lol.