Stock Torque specs and Accuracy

Discussion in 'Long Range Hunting & Shooting' started by BearDog, Oct 8, 2013.

  1. BearDog

    BearDog Well-Known Member

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    A few weeks back I had taken my rifle into a gunsmith to have the riveted extractor swapped out on my .300 Win Mag Sendero. The gunsmith, who I was very impressed with, said he took the liberty of fixing a couple other things (at no extra charge) he had noticed. One of those things was tightening the stock down to 55 in/lbs. I have a McMillan Game Scout on my Sendero, and had it tightened to 45in/lbs, but he claimed for the magnum calibers it should be at 55. Having spent a little time at the range this past weekend, I wasn't shooting as tight groups as a typically do. I don't want to make excuses, and I may have been just having an off day, but it brings to light a couple questions.

    Does changing the torque on the stock to action change point of impact, and do rifles have a "sweet spot" when it comes to torque that will have an effect on groups?
     
  2. dragman

    dragman Well-Known Member

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    for what it's worth here is my 0.02

    in an unbedded gun, one that only has recoil lug done, or a poorly bedded one I can see the bennifit of playing with torque specs to find the sweet spot. and how that can make a huge difference in accuracy and consistancy.
    If a rifle is bedded correctly, or in say a aluminum chassie where all contact is metal on metal then is shouldn't matter as long as it's tight enough to stay at the same spec. Personally I don't set mine to any particular ft/lbs I crank them tight and leave them. and I have never had a problem if the gun was bedded properly.
     

  3. sendero72

    sendero72 Well-Known Member

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    Call the stock manufacturer. My old Sendero had a HS Precision stock which required 65 inch pounds. Remington stated only 45 on their website. 65 inch pounds was the accuracy spot!
     
  4. gamehawker

    gamehawker Well-Known Member

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  5. BearDog

    BearDog Well-Known Member

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    Thanks for the response guys. I know what McMillan recommends for torque specs, my question was more directed towards whether or not the amount of torque applied to a stock would have an effect on group size consistency? I was more after that than a specific in/lb because of what I was seeing from my groups this past weekend. I appreciate the responses!
     
  6. J E Custom

    J E Custom Well-Known Member

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    Each rifle/stock combination requires slightly different torque.

    The best way I know to find it is to start at minimum torque (Somewhere around 40 Inch Pounds)
    and increase by 5 lb increments checking accuracy as you shoot.

    The torque specks for a given stock are normally Maximum and should not be exceeded.

    The answer to your question is, YES. Torque can effect accuracy.

    J E CUSTOM
     
  7. BearDog

    BearDog Well-Known Member

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    Interesting. Thanks for the advice. When I shot after it was torqued to 55 there was no change in point of impact. Is there any reason to think that easing it back to 45 will change the POI, or does the change in torque really just have an effect on harmonics?
     
  8. J E Custom

    J E Custom Well-Known Member

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    If the bedding is great and the stock has pillars. It should not change the POI very much.

    But seldom is the bedding perfect and if it is not pillar bedded it will/can change with any change
    in torque.

    Never use more torque than necessary to get the best accuracy, Why; More torque can compress
    the stock material, flex the action and effect the actions changes in heat/cold.

    If it shoots good at 55inch pounds leave it. Harmonics are effected by every change But the POI
    changes may be so small that they only show up at longer distances.

    J E CUSTOM