Single digit SD not good enough.

Discussion in 'Reloading' started by Nimrodmar10, Oct 16, 2011.

  1. Nimrodmar10

    Nimrodmar10 Well-Known Member

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    Still fighting the Sendero in 7 RUM. It won't shoot the Berger so I've dropped to a 150 gr. Swift Scirocco and a 150 gr
    Nosler Balistic Tip. My five shot groups with US869 is only showing an extreme spread of 13 fps and a standard deviation of 7. This should be some great loads but my group sizes are still running just over an inch. I had hoped for better. Any ideas?
     
  2. highridge1

    highridge1 Well-Known Member

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    Are your action screws properly torqued? I go 45 inch lbs on both. Is the barrell floated with no contact? What is your trigger weight? That rig should be able to go well under a inch. Are you spacing the shots to keep barrel temp down?
     

  3. milanuk

    milanuk Well-Known Member

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    If your gun isn't grouping under an inch @ 100yds, it likely has nothing at all to do with your ES/SD.
     
  4. boomtube

    boomtube Well-Known Member

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    "If your gun isn't grouping under an inch @ 100yds, it likely has nothing at all to do with your ES/SD. "

    Roger that. An ES of 13 fps is quite good; you could have an ES of 1 and get even worse groups. A load that's wrong for the rifle won't shoot good no matter how precisely it's made.
     
    Last edited: Oct 16, 2011
  5. Boss Hoss

    Boss Hoss Well-Known Member

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    Edited
     
    Last edited: Nov 7, 2011
  6. DKA

    DKA Well-Known Member

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    Got my nephew's working with 96 Gr H 1000 & 165 Gr Nosler Ballistic Tips. :)
     
  7. Nimrodmar10

    Nimrodmar10 Well-Known Member

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    Changed from CCI magnum primers to Federal magnum primers yesterday and the groups tightened right up. A couple of them were one raged hole. Still playing with the seating depth some. Now I'm curious if the Gold Match Federal primers will help even more. The problem is finding them around here.