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Amazing shot

Varmintmist

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The bullet has momentum given to it by the turning of the earth while it's in the gun. It doesn't loose the momentum just because it leaves the barrel. The gun is rotating with the earth and has no force working on it that is different from the bullet since the gun's momentum is continuous, as is the bullet's. And the air is also rotating with the earth, so it does not put any extra force onto the bullet relative to its momentum other than that created by weather. This is a non-issue. Other things must be in play, but not the rotation of the earth.

Another way to say it is that the earth, the gun, the bullet, and the air all are rotating together.
They are until the bullet leaves the barrel. After that the earth and the bullet are no longer connected so there is no force exerted on the bullet at that level. It happens to everything not attached to the earth. Newton says the effect of momentum will drop off unless there is a force applied. The impact will be to the right in the Northern Hemisphere if you are shooting north. This is a proven effect not a theory.

Oh, and as a nifty treat, east west does affect a impact. Firing due east you will impact low, west high. There are some who say that a head wind or tail wind doesnt have an effect. However they do. A headwind will cause the impact to be low and a tailwind will cause the impact to be high of your no wind zero. basically the bullet has to travel through more air in a headwind "farther" if you will and like a jet that picks up a tailwind, the bullet travels "faster". You can see that at mid range.


The thing is though, on a known course, the same course, the affect should be null after establishing a no wind zero. East West North or south. Once you get a zero for that range, rifle and ammo, you are good to go. At 1000 yards you are looking at under 4 inches, which is enough to miss if you make any other calls poorly. Good luck getting a no wind zero over 4.4 miles though.
 

Posaune

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They are until the bullet leaves the barrel. After that the earth and the bullet are no longer connected so there is no force exerted on the bullet at that level. It happens to everything not attached to the earth. Newton says the effect of momentum will drop off unless there is a force applied.
Momentum does not disappear unless a force is applied. If no force is there to change something's momentum it will go on forever. The bullet leaving the barrel does not lose momentum because it's not hooked to the gun. It may loose it for some other reason, but it won't do it on its own. Momentum is not a force. Newton says just the opposite: Momentum will continue unless there is a force applied. Einstein proved it in another way, but it's the same effect.
 

Varmintmist

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It doesn't "drop off" however the earths rotation no longer affects it. Which is why if you fire north, the bullet will impact right. The earth rotates east and it rotates faster at the middle than it does at the top or bottom. Nothing is keeping the bullet in the same relative position to the earth. It is fired from point A and point B is no longer in the same position.
 

dbostedo

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It doesn't "drop off" however the earths rotation no longer affects it. Which is why if you fire north, the bullet will impact right. The earth rotates east and it rotates faster at the middle than it does at the top or bottom. Nothing is keeping the bullet in the same relative position to the earth. It is fired from point A and point B is no longer in the same position.
Correct... but I think @Posaune's point is that the bullet shot out of a gun due north is ALSO moving to the right at the same speed as the earth is rotating in that spot (from the point of view of someone in a fixed location in space looking down on this). And it continues to move to the right at that speed during its flight. It doesn't just stop moving right once it leaves the gun.

Ignoring some of the other effects (wind, bullet spin, coriolis) It impacts to the right only because of the difference in the relative rotational speed of the target and gun. I.e. the bullet move right faster than the target did.
 
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Tricia

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Just seeing this now.
Just wow!
 

Varmintmist

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Correct... but I think @Posaune's point is that the bullet shot out of a gun due north is ALSO moving to the right at the same speed as the earth is rotating in that spot (from the point of view of someone in a fixed location in space looking down on this). And it continues to move to the right at that speed during its flight. It doesn't just stop moving right once it leaves the gun.

Ignoring some of the other effects (wind, bullet spin, coriolis) It impacts to the right only because of the difference in the relative rotational speed of the target and gun. I.e. the bullet move right faster than the target did.
Actually, the bullet does not move right more or less than its speed reletive to where it was fired. It impacts to the right because there is no force working on it to keep it in line with the aim point (expected path). It stays at the lateral speed of the ground at the latitude it was fired at. That is not the same ground speed of the impact point. The target moves out from under the bullet simply because the earth is rotating at a different speed at each latitude. You cant ignore the coriolis effect because this IS the coriolis effect.
If one were to lazer aim and zero a rifle at a 1000 yard target due north, then proceed to fire a shot, all things other being null, the bullet would be to the right. In a perfect no wind day from a lazered zero at 1000yards, you will have to come a half min left to hit center.
To say that the rotation of the earth is a non issue is incorrect. "And the air is also rotating with the earth, so it does not put any extra force onto the bullet relative to its momentum other than that created by weather. This is a non-issue. Other things must be in play, but not the rotation of the earth." At 4.4 miles, firing north, the rotation of the earth on its own could account for missing that metal backer they had entirely.

Demonstration of Coriolis Effect​


Let us pretend to be standing at the North Pole and tossing a ball to our friend standing at the equator. While the ball travels through the air, the Earth below it is rotating. Hence, when the ball reaches the equator, it lands in a location somewhere to the west of where you were aiming. The figure below illustrates this example.


Coriolis Effect
 
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dbostedo

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It stays at the lateral speed of the ground at the latitude it was fired at. That is not the same ground speed of the impact point. The target moves out from under the bullet simply because the earth is rotating at a different speed at each latitude. You cant ignore the coriolis effect because this IS the coriolis effect.
Fair point on the coriolis effect - I shouldn't have mentioned it where I did. But the rest IS what I was saying. Maybe we're talking past each other.
 
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Posaune

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Actually, the bullet does not move right more or less than its speed reletive to where it was fired. It impacts to the right because there is no force working on it to keep it in line with the aim point (expected path). It stays at the lateral speed of the ground at the latitude it was fired at. That is not the same ground speed of the impact point. The target moves out from under the bullet simply because the earth is rotating at a different speed at each latitude. You cant ignore the coriolis effect because this IS the coriolis effect.
If one were to lazer aim and zero a rifle at a 1000 yard target due north, then proceed to fire a shot, all things other being null, the bullet would be to the right. In a perfect no wind day from a lazered zero at 1000yards, you will have to come a half min left to hit center.
To say that the rotation of the earth is a non issue is incorrect. "And the air is also rotating with the earth, so it does not put any extra force onto the bullet relative to its momentum other than that created by weather. This is a non-issue. Other things must be in play, but not the rotation of the earth." At 4.4 miles, firing north, the rotation of the earth on its own could account for missing that metal backer they had entirely.

Demonstration of Coriolis Effect​


Let us pretend to be standing at the North Pole and tossing a ball to our friend standing at the equator. While the ball travels through the air, the Earth below it is rotating. Hence, when the ball reaches the equator, it lands in a location somewhere to the west of where you were aiming. The figure below illustrates this example.


Coriolis Effect
I wasn't talking about the Coriolis effect. I was addressing the statement that, somehow, momentum goes away on its own. That does not happen. I also, in an earlier post, agreed that the Coriolis effect was in play. People are putting ideas out under my name that I do not subscribe to. I'm done with this thread. Leave me out of it.
 

James

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So weird. The poles I get.
^ Rotation of the Galaxy?
 

cantunamunch

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It sounds less like shooting and more an iterative series of experiments.

When you talk of 'iterative series of experiments' I can't help but think of these good ol' boys attempting to sight in a Martini Henry at 600 yards.



The shot in the OP was 13 times longer.

The point I'm making is that one has to start with a controllable experiment, which starts with the gunsmith. The Martini Henry, with 3 shots on target out of >30? That's getting pretty close to uncontrollable. A better word would be chaotic.
 
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Andy Mink

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When you talk of 'iterative series of experiments' I can't help but think of these good ol' boys attempting to sight in a Martini Henry at 600 yards.



The shot in the OP was 13 times longer.

The point I'm making is that one has to start with a controllable experiment, which starts with the gunsmith. The Martini Henry, with 3 shots on target out of >30? That's getting pretty close to uncontrollable. A better word would be chaotic.
When is DOES hit, it hits with authority! That's a whole lotta lead making the trip downrange. Considering the rifle hit the field in 1871 and stayed in service through 1918, that's pretty good. A 150+ year old design in a gun that is over 100 years old. I wouldn't want to be standing down there!
 

cantunamunch

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When is DOES hit, it hits with authority! That's a whole lotta lead making the trip downrange.

Sure. Authority. Which makes it Authoritative Chaos.

And all the Quigley shooters prove it with their 1874 Sharps launching almost the same weight bullet double the distance with actual controllable precision. Those are experiments. The Martini video is ... authoritative, chaotic, entertainment.

Considering the rifle hit the field in 1871 and stayed in service through 1918, that's pretty good.

Why is that impressive, other than proving army cheapskatism, double dealing and questionable politics?

Pushing a black powder design with no magazine 20 years past its main battlefield usefulness just means they didn't trust colonial armies worth sh*t.
"Oh, it's just an Indian army fighting Turks in Mesopotamia, give them any old serviceable thing, but we absolutely shouldn't give them modern arms and 1857 proves it".

I wouldn't want to be standing down there!

Sure, I mean that's something I can say about most gun ranges ???
 
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