OCW test with PP 2000 MR .308 @ 200 yards.

Discussion in 'Reloading' started by Lausboob, Jun 4, 2013.

  1. Lausboob

    Lausboob Member

    Messages:
    17
    Joined:
    Mar 29, 2011
    I performed this OCW test @ 200 yards using PP 2000MR. Rifle is a Blaser R8 23.7 " barrel. Any thoughts on what OCW might be ?

    THX, Jimmy
     

    Attached Files:

  2. Bart B

    Bart B Well-Known Member

    Messages:
    2,483
    Joined:
    Dec 25, 2005
    Looks to me like they all shoot pretty good. All are under about 1 MOA.

    I'd shoot three 10-shot groups, one with 46, one with 47 and the last with 48 grains. That'll be a better test, in my opinion.
     

  3. Aldon

    Aldon Well-Known Member

    Messages:
    718
    Joined:
    Sep 4, 2009
    I believe I would go with the 46.2. The method as I understand it is to narrow down a charge that has larger window of accuracy to either side of the given charge to allow for subtle changes in temperature etc that would otherwise swing accuracy greatly. at 46.2 you have such from what I can see. With all the charges hovering around MOA, if this were my rifle I would call it good. You may tighten that up even more if you have not yet tweaked in seating depths.

    Of course, If I am off base in my understanding of OCW, then the above is useless.
     
  4. jasent

    jasent Well-Known Member

    Messages:
    152
    Joined:
    Nov 16, 2010
    I would do an other ocw test with tenth grain increments from 46.0 to 46.7 you may hit you node a little better some where in there
     
  5. Bart B

    Bart B Well-Known Member

    Messages:
    2,483
    Joined:
    Dec 25, 2005
    I would not use any increment smaller than 1/2 grain. Too many shots from adjacent 1/10th grain groups will over lap each other. It even sometimes happens with 1/2 grain increments, especially if each load's accuracy ain't all that great. And many loads with a 3/10ths grain spread in charge weight will shoot no worse than 1/2 MOA at 600 yards; 1/3 MOA at 300 and 1/4 MOA at 200.
     
  6. MontanaRifleman

    MontanaRifleman Well-Known Member

    Messages:
    6,068
    Joined:
    May 21, 2008
    No clear winners IMO. Not with 3 shot groups like that. I would repeat them all @ 300 yds on a no wind day.
     
  7. BountyHunter

    BountyHunter Writers Guild

    Messages:
    4,803
    Joined:
    Jun 13, 2007
    What is your ES and SD? Need a chrono for that.

    That is one of the flaws with OCW, short distance and not using a chrono does not tell you what it might do at longer ranges.

    ES over 25 or so and your LR groups go to pot.

    I would shoot from 46.0 to 47.2 in .3 gr increments over a chrono. Others may disagree but Oh, well.

    Pick the best load and then reshoot for seating depth variation again over a chrono.
     
  8. unvisable

    unvisable Member

    Messages:
    23
    Joined:
    Mar 17, 2005
    Measure each hole in each of the groups horizontally and vertically using the center dot as point 0,0 with positive up or right of center; negative being down or left of center .

    Average each three horizontal measurements and each three vertical measurements to get the group center. That will yield as many ordered pairs as you have 3 shot groups.

    Plot each point on a clean target and connect the points in sequence. you can see how the cwnter of the group is moving around.

    Small movement between centers indicates stability of powder load. That is what you want with OCW.
    Group size for OCW really doesn't mean much as long as all of the shots were "good" shots.

    Picking a charge weight between two or among three is fine. After this you can do seating depth checks.