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Thread: Bipod jump

  1. #1
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    Bipod jump

    Basics for shooting lite weight hunting rifles on bipods at the range
    What causes bipod jump?

    I have always thought it was just the weight that causes the jump on recoil, hence the heavy target rifles. But looking into it is the jump more related to body position?

    Can these types of rifles be shot under free recoil while staying on target or do they really need to be held on fore end

  2. #2
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    Forward pressure on the bipod and hand under the forend if larger calibre will significantly reduce the jump.
    Body position directly behind stock makes a big difference. If your sqewed to the side a bit rifle throws out sideways as well as up.


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    Moa Hunter and flock like this.

  3. #3
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    The shape of the stock can help or be detrimental:
    Compare a straight kimber with the older drop of heel of the weatherby design and you will see what I mean.
    Micky Duck likes this.

  4. #4
    Member janleroux's Avatar
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    Some interesting explanations:

    https://youtu.be/whVH-FaZyQs

    https://youtu.be/fciKcjGKs84

    https://youtu.be/fKSd31KSI88


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  5. #5
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    Incorrect alignment between the butt of the stock and the shoulder.

    Imagine an inverted right angled triangle, the hypotenuse running on the underside. When everything is positioned correctly, this should somewhat resemble the line of force for which recoil will take.

    The vertical portion of the triangle is the buttstock and shoulder interface, whereas the horizontal line should be taken from the muzzle of the barrel, back in a straight line.

    Two critical factors here, bipod height and stock fit. Far too often the bipod is too tall, resulting in the aforementioned triangle being disrupted, and now you have a force that 'lifts' the muzzle, otherwise described as bipod jump.

    Stock fit is the second part, as there are some deisgns of stock (hogback and weatherby) where the drop of heel/toe is significant, and disrupts the triangle.

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    These outdated stock designs were meant for standing or supported shots off sticks, where the drop would provide good alignment straight down the top of the barrel for use with iron sights.

    Whilst the higher comb on the Weatherby stock is there to compensate for the use of scopes, you can't get away from the fact that the stock design forces the muzzle upwards even when correct shoulder positioning is used.

    What you will see on modern aftermarket stocks is a pretty much sttaight line running from where the muzzle will be, back to the top of the buttstock.

    Example of a design optimised for prone shooting off a bipod, the KRG Bravo:

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    What you will also note is the provision of a quick adjustable cheek rest, something which is both an advantage and disadvatage in that it can move.

    Note the USMC Scout Snipers building up their cheek rests and forgoing the adjustable feature:

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    The goal is to create your triangle will transmit recoil in a near straight line back towards you. With correct technique, your bodyweight will counteract the recoil and the rifle will return to postion so you should be able to spot your hits and follow up quickly.

    Use of a rear bag makes this even easier as you can adjust the height of the buttstock by positioning the rear bag under the toe of the stock.

    Good luck.
    Trout, Woody, Marty Henry and 1 others like this.

  6. #6
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    I'm quite interested in the replies thus far.
    I've watched video footage of myself shooting, and note a jump of about 2-3cm of the bipod feet, the rifle goes directly up and backwards slightly, then resets in the same spot it was fired from.
    I've noted my body position and reviewed youtube info of competition shooters/army etc, and think that getting weight further forward on the rifle may help.
    Question I have is, if you're accurate - is the jump a problem?
    And why is the non trigger hand not used on the for end to control the lift?

  7. #7
    Member 199p's Avatar
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    The most important bit is being constant, if your bipod jumps 3 feet in the air but you can shoot little groups all day then its not an issue, if your shooting all around the paper then its an issue
    Konus binoculars " The power to imagine"

  8. #8
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    Quote Originally Posted by thejavelin View Post
    I'm quite interested in the replies thus far.
    I've watched video footage of myself shooting, and note a jump of about 2-3cm of the bipod feet, the rifle goes directly up and backwards slightly, then resets in the same spot it was fired from.
    I've noted my body position and reviewed youtube info of competition shooters/army etc, and think that getting weight further forward on the rifle may help.
    Question I have is, if you're accurate - is the jump a problem? -I think you already know the answer to that one
    And why is the non trigger hand not used on the for end to control the lift?
    I shoot a ultralight 270WSM and tried the free recoil position (ie no hand on the fore) and my groups nearly doubled in size, not saying one way is right and one way is wrong but you need to do what works for you and your rifle and in my experience consistency is key, no matter what you do it needs to be repeatable
    thejavelin, Trout, mikee and 5 others like this.
    #DANNYCENT

  9. #9
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    Ive gone from a Weatherby Vanguard in 270wsm shooting 130g SST's @3200fps to a lighter Kimber Montana 7mm wsm shooting 162g ELD-X lighter gun producing more energy yet due to stock design, the Kimber moves waaaay less

  10. #10
    Sending it Gibo's Avatar
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    Quote Originally Posted by 199p View Post
    The most important bit is being constant, if your bipod jumps 3 feet in the air but you can shoot little groups all day then its not an issue, if your shooting all around the paper then its an issue
    He mentioned staying on target
    199p likes this.

  11. #11
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    Quote Originally Posted by janleroux View Post
    Some interesting explanations:

    https://youtu.be/whVH-FaZyQs

    https://youtu.be/fciKcjGKs84

    https://youtu.be/fKSd31KSI88


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    Yeah seen these, some good information.

  12. #12
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    It seems to me that reducing muzzle jump with a straighter stock must increase felt recoil. The older drop design send the energy upward and with the straight stock its all coming at us. People who love the Sako 75 stock for reduced recoil then must be accepting more tendency to jump?
    top of the south likes this.

  13. #13
    Member Steve123's Avatar
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    The other option is to get rid of the bipod altogether. Try using a bag under your front hand instead.
    Woody likes this.

  14. #14
    Member Ftx325's Avatar
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    With the 338 lap I rest the bipod on something soft like a bag or even just on the grass and jumps way less than on a solid object like a table top .
    It's a full carbon rifle with a hunter style stock so butt pad is lower than Barrel so acts as a perfect hinge point under considerable recoil . The rifle weighs around the same as my Tikka 308 .
    I have tried several ways of holding the rifle to attempt to reduce jump but have settled on just making sure the bipod is loaded forward and hold the front of the stock like a standing shot . I have come to the conclusion that no matter what I do the rifle is powerful enough that I can have very little effect on jump short of a softer bipod rest .
    It is a little frustrating watching the vids of the guy's shooting 338 with their alloy chassis rifles with straight line stocks and they barely move, but that's how much stock design and rifle weight effect the outcome every time you pull the trigger.
    born to hunt - forced to work

  15. #15
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    Quote Originally Posted by Ftx325 View Post
    With the 338 lap I rest the bipod on something soft like a bag or even just on the grass and jumps way less than on a solid object like a table top .
    It's a full carbon rifle with a hunter style stock so butt pad is lower than Barrel so acts as a perfect hinge point under considerable recoil . The rifle weighs around the same as my Tikka 308 .
    I have tried several ways of holding the rifle to attempt to reduce jump but have settled on just making sure the bipod is loaded forward and hold the front of the stock like a standing shot . I have come to the conclusion that no matter what I do the rifle is powerful enough that I can have very little effect on jump short of a softer bipod rest .
    It is a little frustrating watching the vids of the guy's shooting 338 with their alloy chassis rifles with straight line stocks and they barely move, but that's how much stock design and rifle weight effect the outcome every time you pull the trigger.
    I reckon guys would be lining the block to swap your carbon stock for something heavier,more user friendly....heavy laminated /plywood look like a million bucks and just plain old work.... you could od a lot worse than ask and see whats on offer.

 

 

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