Bullet Baring Surface- How Do You Measure It ??

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Down Under Hunter, Nov 23, 2007.

  1. Down Under Hunter

    Down Under Hunter Well-Known Member

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    Just about to start getting real serious about loading a consistantly accurate round for my 338. I was told that measuring the projectiles baring surface was important so I just want to get clear how best to do it ?? Where are the measurements taken from exactly ??

    Thanks all !

    DUH
     
  2. Gene

    Gene Well-Known Member

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    Bullet bearing surface

    Get yerself two identical Stony Point or Davidson comparator nosepieces for the caliber you want. Attach them to a caliper. One goes over the bullet point, other over the bullet base. Slide your caliper and measure, sorting bullets into groups. Cull out bullets having the widest discrepancy.
     

  3. royinidaho

    royinidaho Writers Guild

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    dnundr;

    Shoot it straight up, really straight, catch it in a bucket on the way down then measure the length of the marks.:D

    What Gene said is a bit better.;)

    If you're in a hurry set your caliper to the Bore size and slip it over the ogive and make a mark. To make the mark just turn the bullet slightly in the caliper. Slip it over the base and make a mark. A PITA but will do if in a hurry or are impatient waiting the stoney point order to arrive.:rolleyes:

    I use a sinclair gizmo that looks like a hex nut. and insert the bullet both ways. Not as good, easy or as fast as the stoney point method though.
     
  4. Down Under Hunter

    Down Under Hunter Well-Known Member

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    Roy and Gene,

    Thanks for the handy tip. I'll buy one straight away !

    Thanks boys !

    DUH
     
  5. Down Under Hunter

    Down Under Hunter Well-Known Member

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    PS-- Can anyone give me a link to a 338 cal Stoney Point bullet comparator please so I can order one.

    Many thanks

    DUH
     
  6. AJ Peacock

    AJ Peacock Well-Known Member

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    Stoney point was purchased by Hornady not too long ago.

    You will need 2 of these MidwayUSA - Hornady Lock-N-Load Bullet Comparator Insert 338 Diameter

    and 2 of these
    MidwayUSA - Hornady Lock-N-Load Bullet Comparator Body

    A good digital caliper makes using these very quick and accurate.

    Instead, I purchased the headspace kit and the comparator kit, so I could measure all calibers etc. The headspace kit comes with a .330 insert, so measuring the baring surface for 338 can be done without a second .338 insert. The .338 insert is actually .330 and is marked as such.

    MidwayUSA - Hornady Lock-N-Load Headspace Gage 5 Bushing Set with Comparator
    MidwayUSA - Hornady Lock-N-Load Bullet Comparator Complete Set with 14 Inserts



    AJ
     
  7. Down Under Hunter

    Down Under Hunter Well-Known Member

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    AJ

    If I was going to only use it for my 338 which is the cheapest way to go ? I think my friend has a headspace guage ? Many thanks for your help

    DUH
     
  8. phorwath

    phorwath Well-Known Member

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    I just ordered two of the "Hornady Lock-N-Load Bullet Comparator Complete Set with 14 Inserts" from Amazon.com for $36.14 per set. Free shipping. They were the last two Amazon.com had in stock. But that's not to say they won't get some more in. Guess I'll be able to measure the bearing surface on all the calibers now. Midway's price for a single set was $58.99.


    I'll let AJ reply, but I think the minimal purchase to measure bearing surface on your 338 bullets is:

    You will need to purchase 2 of these:
    Hornady Lock-N-Load Bullet Comparator Insert 338 Diameter

    and 2 of these:
    Hornady Lock-N-Load Bullet Comparator Body

    Will cost about $43.60 from MidwayUSA, plus shipping costs.
     
  9. Down Under Hunter

    Down Under Hunter Well-Known Member

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    Thanks boys for that. I think I am clear on that now.

    Thanks once again for steering me in the right direction.

    Cheers

    DUH
     
  10. AJ Peacock

    AJ Peacock Well-Known Member

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    DUH,

    If you load for other calibers, I'd recommend getting both of the complete kits. However, if funds are short you could start with just the comparator kit and measure base to ogive (which is better than nothing). Keep you eyes open for a cheaper kit, I think the kit was cheaper before Hornady bought Stoney Point, you might find the kit cheaper somewhere?

    What these kits allow you to do is measure the distance between 2 .330 holes with the bullet in the center (pretty simple for the $). There are other ways to do it, but they are not as easy. Sinclair also carries a 'very similar' product. 2 bodies and 2 inserts would be around $40.

    HTH

    AJ
     
  11. AJ Peacock

    AJ Peacock Well-Known Member

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    One more thing, from what I've read, measuring baring surface is really not necessary until you get beyond 800yds and really beyond 1000yds

    AJ