Rifling and Muzzle Rise

Discussion in 'General Rifle Discussion' started by BillM, Jul 10, 2013.

  1. BillM

    BillM Active Member Supporter

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    Shamelessly pulled this from another forum. It is part of a larger
    post about muzzle brakes--but this clip is not out of context.


    Comments? Personally I am just a wee bit skeptical.:)

    "The actual physics that cause the barrel to rise is the the spin on the bullet (i.e. the twist rate) - change the rifling to the other direction and the barrel would go down not up. I think that the concept of rifling a barrel must have been invented in the northern hemisphere by right handed people."
     
  2. texaswoodworker

    texaswoodworker New Member

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    Interesting theory. Subscribed. I'd like to hear more about this.
     

  3. MisterMcCool

    MisterMcCool Well-Known Member Supporter

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    If the projectile comes out at a downward spin, change the length a bit and it comes out at an upward spin. Manufacturers don't cut barrels at a specific exit angle.
     
  4. BillM

    BillM Active Member Supporter

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    I thought it was worth sharing. It does bring to mind one question---
    Smoothbore guns (old musket, shotgun), having no rifling twist
    would by this theory have neither muzzle rise nor dip.

    From my own observation over the years, this doesn't seem to be
    the case. Odd.
     
  5. MisterMcCool

    MisterMcCool Well-Known Member Supporter

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    Cannons too.
     
  6. texaswoodworker

    texaswoodworker New Member

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    This got me thinking. We could possibly calculate this by finding the rotational force of a given bullet (Rotational force = moment of inertia x rotational acceleration) and then finding the direction the force is going and comparing that that to a bullet spinning in an opposite direction.

    Here's what I think the results would be. I think any upward or downward force that the bullet puts on the barrel would be negligible. The reason for the muzzle flip is you. On a gun (both long gun and hand gun) your hands are positioned mostly on the bottom of the gun, below the barrel. on a long gun, your shoulder is also positioned mostly below the barrel. This means you act as a fulcrum, and you cause the muzzle rise.

    Shoot a gun upside-down (not advisable) and you would most likely still see muzzle rise.
     
  7. MisterMcCool

    MisterMcCool Well-Known Member Supporter

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    Last edited: Jul 10, 2013
  8. SSGN_Doc

    SSGN_Doc Well-Known Member

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    BS. Some guns do have left hand twist, and others have right hand twist, smooth bores have no twist. They all have muzzle climb. Probably more to do with bore height, stock angle/drop at the comb, and physical contact with the gun that drives the muzzle upward.
     
  9. BillM

    BillM Active Member Supporter

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    Actually, the muzzle goes down when you shoot one upside down. At least
    on a revolver and a 1911 (watch that slide!)--both of which I have tried.

    Reason? Because with the gun upside down, the resistance your body imparts
    (the fulcrum) is now ABOVE the centerline of the bore.

    Come to think of it, I've also shot my 1100 Remington upside down.
    Little bit of muzzle dip with that one too.
     
  10. texaswoodworker

    texaswoodworker New Member

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    That would be correct.

    On the 1100, were your hands above or below the bore? I'm guessing that they were more above it.
     
  11. mrm14

    mrm14 Active Member

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    Timed muzzle brake on a large cartridge caliber in a rifle is your friend.
     
  12. BillM

    BillM Active Member Supporter

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    Actually--I was firing it held upside down above my head. Watched
    a little too much Tom Knapp on Impossible Shots.:)

    Recoil was pretty straight, but there was just a bit of muzzle dip. Not
    difficult to shoot at all. Now--HITTING clays shooting that way, not so
    easy. I'm guessing Tom practiced that shot just a bit.
     
  13. Vikingdad

    Vikingdad New Member

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    Take a tube and bend it into a perfect "S" shape. Put a pivot in the center that allows flow from the pivot/stand through the "S" tube. Now submerge the device in a tank of water and pump water through it and out the ends of the "S". It rotates in a counter-clockwise direction (if viewing it as the "S" is properly oriented).

    Next suck water into the device at the same rate. What happens? It still rotates but in which direction? Is the direction of rotation caused by the water flowing into the ends of the "S", or is it caused by the centrifugal force of the water pushing on the curves in the "S"?


    The experiment has nothing to do with the OP, I have always just wondered what the answer to the puzzle is.:p


    Muzzle rise is a direct result of the centerline of the barrel being well above the shooter's wrist, which becomes the fulcrum causing the muzzle to rotate (not rise) off of the wrist. This is the basis for the Chiappa Rhino with the round being fired from the lowest chamber on the cylinder rather than the highest chamber resulting in greatly reduced rotation.
     
  14. gunnut07

    gunnut07 New Member

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    muzzle climb is because of recoil.

    It really is simple. For ever action there is an equal and opposite reaction.

    Your shoulder is not flat and square to the boar is it? Nope so it acts like a pivot point. Not all guns have upward muzzle climb either. Look at an AK ever see the muzzle break on it? They are tilted to one side.

    Though Every gun must have recoil to be accurate.

    I built a 22 K-Hornet and put a 1.5" 28" barrel on it thinking it would be the most accurate gun ever and look cool too. It had zero recoil I mean you could put it on the rest and set the trigger off and it wouldn't move. That rifle had worse groups than a 6" barreled shot gun shooting bb shot at 60 yards. I had the barrel turned down to a more acceptable contour same barrel and everything. We did this by turning it and shooting it the more recoil we got the better it shoot until we got a 5 shot .02" 100 yard group.
     
  15. austin92

    austin92 New Member

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    What does "timed" muzzle brake mean? First time I've heard that, just curious.
     
  16. BillM

    BillM Active Member Supporter

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    On a muzzle brake with top/side holes (not the type with holes all around)
    you rotate the brake to cancel the recoil force vectors.

    Typically for a right handed shooter the gun recoils up and to the right.

    Rotating the brake clockwise (looking from the butt) aligns the top vent holes
    to cancel both the up recoil, and that little flip to the right. Most of my
    AR's with brakes have the "top" of the brake at somewhere around the
    1 o'clock position.
     
  17. robocop10mm

    robocop10mm Lifetime Supporting Member Lifetime Supporter

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    That person is an idiot. If he had the first clue he would understand. It is a product of geometry and leverage
     
  18. trip

    trip New Member

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    Recoil can't be be cancelled. Felt recoil maybe?
     
  19. therewolf

    therewolf New Member

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    OK, let's say you have standard 4-groove rifling. Wouldn't the barrel also

    be inclined to twist CCW, because only one groove and land is facing

    up at the end of the barrel.
     
  20. KG7IL

    KG7IL Active Member

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    Direction of rifling twist has no effect. All forces due to bullet rotation and twist are equalized in the vertical component.

    Bore Axis relation to the grip causes this rise.
     

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