How to Identify optics problems?

Discussion in 'Long Range Hunting & Shooting' started by dixie175, Feb 12, 2010.

  1. dixie175

    dixie175 New Member

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    I have a 7mm RM in a sendero SF with a leupold mark4 PR 4.5-14x40 30mm SF. I loaded up 3 162gr hornady sst bullets with 63.5 of rl 22 shot dead on on the first shot, low on second, a little left on the third. Loaded up 65 grains of rl 22 on the next day, cleaned my barrel, and taped new target over the old one. Shots 1,2,and 3 went in the same holes as 1,2,and 3 of the prior day. I looked through old targets and there is a significant history of this gun doing this. This gun almost always places the first second and third holes in the same places at the start of a new day. Is this optics problems? Shoots no more than a 1inch group most of the time and occasionally 3/8 to 1/2 inch groups with really light loads.
     
  2. MTBULLET

    MTBULLET Well-Known Member

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    I thnk I'd look more to bedding or loose action screws if this is a constant problem. Also, what does it do after the first 3 shots ?
     

  3. 3fingervic

    3fingervic Well-Known Member

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    Doesn't sound like a scope problem to me. How deep are you cleaning? Bare metal?
     
  4. bigngreen

    bigngreen Well-Known Member

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    Do you clean after every trip to the range? I found I was over doing the cleaning and it took a few rounds to settle it down, I stopped stipping it all the way down everytime I clean and the last patch is Kroil and it seems that now that that has gone away but I ahve only done it twice but it got rid of my cold bore shot going slightly low and left. Other than that, bedding or how you settle down while shooting.
     
  5. clamb4

    clamb4 Well-Known Member

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    I have a 7mm mag that does almost the same thing with a clean barrel. It will string the first three shots and then group 5/8" until the barrel gets real dirty maybe 50 to 60 rounds later. You might try shooting with a fowled barrel.
     
  6. liltank

    liltank Well-Known Member

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    +1 to the, "too clean of a barrel."

    Tank
     
  7. dixie175

    dixie175 New Member

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    It does this if it is clean or dirty. The more shots in one session it settled into a pretty tight group, but the group is to the left. Like I said, the first shot of each day goes in the same hole 95% of the time. The action and floor plate is bedded. The recoil lug is bedded in the rear and .010" from front and bottom. It really seems strange that it will duplicate shots shots like this. I've made three quick shots at times and waited up to 30 min. between shots at times with no difference. Something is settling back to origional condition, but it takes a long time(>30min) to do it.
     
  8. long450

    long450 Well-Known Member

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    Sounds like a stock bedding or maybe bolt touching stock issue. Scope problems will not repeat 1,2, and 3. They will be all over the place. Change the scope out and I bet it still does it. A simple test would be to take the action out of the stock and place a piece of thin plactic (old credit card) under the action by the lug and see if it changes the pattern. You can look at the bolt and see if it is touching the stock. I have seen the bolt touching cause problems, but I do not remember them being repeatable.
     
    Last edited: Feb 12, 2010
  9. 4bycamper

    4bycamper Well-Known Member

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    Doesn't sound like a scope problem to me either. Sounds like a barreled action problem. Maybe something really strange like the barrel not in line with the bolt.

    I had a Winny that was like that. Never would make nice groups until the barrel was warm to hot. No repeatable shots, just 2" groups for the first three. Then the rifle would settle down and shoot under an inch until the barrel was too hot to touch. :)

    Seems the action was not drilled and threaded centered-on and in-line with the bolt. So the barrel was at a little angle to the receiver.

    Best of luck with that.