I must apologise. I misread the post and it took a few minutes for what you were trying to say to sink in. The bore is pointed upward in relation to the breach and the bullet would rise above the line of sight, but would never actually be above the line of the bore, since the bore is pointed up slightly.
Why do bullets rise?
- Thread starter chasep255
- Start date
I must apologise. I misread the post and it took a few minutes for what you were trying to say to sink in. The bore is pointed upward in relation to the breach and the bullet would rise above the line of sight, but would never actually be above the line of the bore, since the bore is pointed up slightly.
Bullets never rise above the line of the bore!!!!!!!!! If you took a same weight bullet as being fired and hold it at bore hieght, and fired one with the barrel parralel to the ground and released the held bullet at the same time one was fired from the gun, they would hit the ground at the same time.
Bob
Bob
While we are being picky, the dropped bullet and the shot bullet might not hit at exactly the same time, as they aren't in vacuum, but atmosphere. Odds are they'd offer different aspects to the air as they fell, so the drag would differ, and the acceleration rates wouldn't be exactly the same.
They'd be very close though.
Just remember that calculus problems in school tended to leave out aerodynamic drag. It affects downward velocity as well as forward.
They'd be very close though.
Just remember that calculus problems in school tended to leave out aerodynamic drag. It affects downward velocity as well as forward.
Maybe because he got his answer in the first seven minutes from the first two posts and moved on?TENFAN said:
Major Dave sez, "The barrel is NOT angled upward...". Yes, it is, (with respect to the local plane of the earth) otherwise we would never be able to hit anything above the height of the muzzle from the ground, and there wouldn't be two points at which the bullet crosses the sight line. Your other statements and reasoning are sound, but the post title isn't.
spacecoast
New member
Only in a vacuum. A parabola is only an approximation otherwise (but a pretty good one).
Major Dave (retired)
New member
Mal H
Picture in your mind a chamber reamer being positioned into a barrel blank so that the long axis of the reamer is angled downward in relation to the long axis of the barrel blank. IF chambers were reamed in this fashion, the barrel would be angled upward, as you indicate. Right? Would there be any other way to build a rifle, pistol, or artillery cannon to achieve a barrel that was angled upward?
Or, now that I think of it, if the chamber reamer long axis was concentric with the long axis of the bore of the barrel blank, would the back end of the barrel blank be threaded at an angle to produce a barrel that was angled upward when screwed into the action?
If my two tries at explaining how to achieve an upward pointing barrel are both wrong (and I think they are), then just how does one construct such a configuration?????
Any gunsmiths reading this post (I am not one)?
Comments from gunsmiths, please. Comments from others who feel qualified to clarify the "upward pointing barrel phenomenon", and how to achieve it.
Have any of you who have experience building firearms ever heard of any specifications as to what upward angle must be machined into the juncture between the forward end of an action and the rearward end of a barrel to end up with a correctly upward pointing barrel?
Or maybe - as a 3rd possibility- the machine which bores out the barrel blank to the correct caliber dimension, starts off-center LOW in the blank, and exits the muzzle end HIGH, off-center? That would produce an "angled upward bore, wouldn't it? But then, you would need "a witness mark", to be sure that you had the barrel Top Dead Center (TDC) in the right place when you mated it to the receiver...otherwise, you would have a barrel that was canted, borewise. That would really mess up both your near zero, and your far zero.:barf:
Someone, somewhere, PLEASE convince me that barrels are upward pointing, rather than gun sights being downward pointing.
OR, explain to me how to "Zero the barrel", rather than "Zero the sights".
I'm just saying.....
Picture in your mind a chamber reamer being positioned into a barrel blank so that the long axis of the reamer is angled downward in relation to the long axis of the barrel blank. IF chambers were reamed in this fashion, the barrel would be angled upward, as you indicate. Right? Would there be any other way to build a rifle, pistol, or artillery cannon to achieve a barrel that was angled upward?
Or, now that I think of it, if the chamber reamer long axis was concentric with the long axis of the bore of the barrel blank, would the back end of the barrel blank be threaded at an angle to produce a barrel that was angled upward when screwed into the action?
If my two tries at explaining how to achieve an upward pointing barrel are both wrong (and I think they are), then just how does one construct such a configuration?????
Any gunsmiths reading this post (I am not one)?
Comments from gunsmiths, please. Comments from others who feel qualified to clarify the "upward pointing barrel phenomenon", and how to achieve it.
Have any of you who have experience building firearms ever heard of any specifications as to what upward angle must be machined into the juncture between the forward end of an action and the rearward end of a barrel to end up with a correctly upward pointing barrel?
Or maybe - as a 3rd possibility- the machine which bores out the barrel blank to the correct caliber dimension, starts off-center LOW in the blank, and exits the muzzle end HIGH, off-center? That would produce an "angled upward bore, wouldn't it? But then, you would need "a witness mark", to be sure that you had the barrel Top Dead Center (TDC) in the right place when you mated it to the receiver...otherwise, you would have a barrel that was canted, borewise. That would really mess up both your near zero, and your far zero.:barf:
Someone, somewhere, PLEASE convince me that barrels are upward pointing, rather than gun sights being downward pointing.
OR, explain to me how to "Zero the barrel", rather than "Zero the sights".
I'm just saying.....
Last edited:
Does it matter if sights point downward relative to the barrel, or the barrel points upward relative to the sights?
Since the sights are usually above the bore, they have to be set up to converge. (Side mounted or canted sights introduce lateral parallax to the problem, but it's the same concept.)
Since the sights are usually above the bore, they have to be set up to converge. (Side mounted or canted sights introduce lateral parallax to the problem, but it's the same concept.)
Major Dave (retired)
New member
I don't know,
but I know that ONLY the sights can be moved, in order to change their angle. There is no need, therefore, to make adjustments to the barrel.
And that seems to me to be a good thing, because making adjustable barrels would be a design engineering nightmare, don't 'cha think?
but I know that ONLY the sights can be moved, in order to change their angle. There is no need, therefore, to make adjustments to the barrel.
And that seems to me to be a good thing, because making adjustable barrels would be a design engineering nightmare, don't 'cha think?
I don't think anybody has suggested adjusting the barrel.
Whether you look at the barrel as pointing upward to the sight line, or the sights as being angled down toward the barrel to force the shooter to elevate the muzzle, the effect is the same. The line of the bore points higher than the line of the sights.
Whether you look at the barrel as pointing upward to the sight line, or the sights as being angled down toward the barrel to force the shooter to elevate the muzzle, the effect is the same. The line of the bore points higher than the line of the sights.
mikejonestkd
New member
A bit of reading material on the subject:
http://www.rifleshootermag.com/shooting_tips/ballistics_0303/
http://www.rifleshootermag.com/shooting_tips/ballistics_0303/
Major Dave (retired)
New member
Another comment for Mal H...
We are all easily able to hit anything above the muzzle simply by swinging the muzzle upward as a part of aiming at the target. We, the shooters, angle the barrel upward, or downward, which HAS NOTHING TO DO with the OPs initial question. His question was about the relationships between the line of bore, the line of sight, and the trajectory of the bullet.
He didn't understand how the trajectory of the bullet could cross the line of sight twice, but never rise above the line of bore. That has nothing to do with shooting at a target above the muzzle as the shooter stands on "...the local plane of the earth".
We are all easily able to hit anything above the muzzle simply by swinging the muzzle upward as a part of aiming at the target. We, the shooters, angle the barrel upward, or downward, which HAS NOTHING TO DO with the OPs initial question. His question was about the relationships between the line of bore, the line of sight, and the trajectory of the bullet.
He didn't understand how the trajectory of the bullet could cross the line of sight twice, but never rise above the line of bore. That has nothing to do with shooting at a target above the muzzle as the shooter stands on "...the local plane of the earth".
Years and years and years of poor illustrations of a gun, a target and the line of bullet path has brainwashed and confused many people into thinking the barrel is pointed at the target and the bullet goes up and then down in an arc. In reality only the sights are pointed at the target and the barrel is angled up enough to cause the bullet to hit at the aiming point. At no time will the bullet rise above the bore of the rifle because it starts to fall as soon as it clears the muzzle. It is going forward but from a straight line from the ore out to infinity the bullet will be seen to be dropping. It matters not how you adjust your sights, unless you have one screwed up muzzle the bullet can only go out and down. Ain't quantum mechanics folks, just plain old Newtonian Physics.
We REALLY need more smilies... I need the one of the smilie eating popcorn.. this is getting really GOOD!!! 
I've learned so many cool things...
Texans don't understand ballistics.
A .22 rimfire sighted in at 25yds will be dead on at 100yds..
Yeast makes bullets rise.
If you fire a bullet in a vacuum, the vacuum doesn't work anymore..
I'm lovin it...
I've learned so many cool things...
Texans don't understand ballistics.
A .22 rimfire sighted in at 25yds will be dead on at 100yds..
Yeast makes bullets rise.
If you fire a bullet in a vacuum, the vacuum doesn't work anymore..
I'm lovin it...
Major Dave - sorry, but I have to say What?!
No one is even remotely suggesting that the barrel is adjusted in any way, or the bore is reamed other than true to the centerline.
The barrel must be tilted up slightly if the bullet is going to make an arc to a target which is at an equal height to the muzzle above the ground.
The act of making the line of sight of the sights slightly tilted downward with respect to the bore axis forces the barrel to be tilted up by the shooter as he aims at the target.
Apparently you read a whole lot more into the OP's question than I did. He said, "However most ballistics data I see indicates that the bullet actually rises." You said, "His question was about the relationships between the line of bore, the line of sight, and the trajectory of the bullet." I think that assumed more than he actually asked.
No one is even remotely suggesting that the barrel is adjusted in any way, or the bore is reamed other than true to the centerline.
The barrel must be tilted up slightly if the bullet is going to make an arc to a target which is at an equal height to the muzzle above the ground.
The act of making the line of sight of the sights slightly tilted downward with respect to the bore axis forces the barrel to be tilted up by the shooter as he aims at the target.
Apparently you read a whole lot more into the OP's question than I did. He said, "However most ballistics data I see indicates that the bullet actually rises." You said, "His question was about the relationships between the line of bore, the line of sight, and the trajectory of the bullet." I think that assumed more than he actually asked.
OK, I understand and agree with the above. We have understood this for years.
But here is the question: I watched " Between The Crosshairs " on the history channel. To get this clearly in mind, a sniper in Iraq was explainning their shooting. I'm not going to mention his name so that an enemy doesn't track him or his family down. They were shooting the Remington 308 with a heavy barrel and a Leupold 10X scopes with mil dots and target knobs. They were on a tall building and shooting out to 800 meters or yards, hitting moving targets as insurgents ran accross the street.
The Sniper and his spotter noticed a fellow soldier skylighting himself on top of a building. He radioed down and told that fellow to get down. A few minutes later he was up skylighting himself again. And bang, the soldier was shot an killed. The sniper and his spotter found the enemy sniper on a balcony. The distance was 1350 yards. The sniper worried that the enemy sniper would kill more American Soldiers was going to scare hin by sending a bullet his way.
He cranked his elevation knob to the max. He then applied some Kentucky windage.He aimed 13' above him and 4' into the wind. When he pulled the trigger the enemy sniper was hit COM and died.
Explainning the shot he said that the bullet driffed to the right due to bullet spin. HE ALSO SAID THAT THE BULLET RAISED DUE TO GYROSCOPICS.
This is what I don't understand. I know that in girls softball the pitcher can make the ball dance which includes raising at the plate fooling the batter in a swing and a miss.
Any thoughts?
But here is the question: I watched " Between The Crosshairs " on the history channel. To get this clearly in mind, a sniper in Iraq was explainning their shooting. I'm not going to mention his name so that an enemy doesn't track him or his family down. They were shooting the Remington 308 with a heavy barrel and a Leupold 10X scopes with mil dots and target knobs. They were on a tall building and shooting out to 800 meters or yards, hitting moving targets as insurgents ran accross the street.
The Sniper and his spotter noticed a fellow soldier skylighting himself on top of a building. He radioed down and told that fellow to get down. A few minutes later he was up skylighting himself again. And bang, the soldier was shot an killed. The sniper and his spotter found the enemy sniper on a balcony. The distance was 1350 yards. The sniper worried that the enemy sniper would kill more American Soldiers was going to scare hin by sending a bullet his way.
He cranked his elevation knob to the max. He then applied some Kentucky windage.He aimed 13' above him and 4' into the wind. When he pulled the trigger the enemy sniper was hit COM and died.
Explainning the shot he said that the bullet driffed to the right due to bullet spin. HE ALSO SAID THAT THE BULLET RAISED DUE TO GYROSCOPICS.
This is what I don't understand. I know that in girls softball the pitcher can make the ball dance which includes raising at the plate fooling the batter in a swing and a miss.
Any thoughts?
To address the show you watched. I think there was some mixing of stories perhaps to enhance or whatever those shows do.
There are several videos on the link below. Not sayin any of them are any more or less than the show you watched.
http://www.military.com/video/speci...ipers/one-mile-sniper-kill-shot/665219835001/
My thoughts on the Gyroscopics are simply that such a phenomenon probably does occur, but at any thing but very long ranges not noticeable. And the projectile would not rise above the line of bore.
There are several videos on the link below. Not sayin any of them are any more or less than the show you watched.
http://www.military.com/video/speci...ipers/one-mile-sniper-kill-shot/665219835001/
My thoughts on the Gyroscopics are simply that such a phenomenon probably does occur, but at any thing but very long ranges not noticeable. And the projectile would not rise above the line of bore.
Major Dave's first post confused me for a moment too, but I see his point. Some people get the idea that with a barrel parallel to the ground the bullet will rise above the bore after leaving the muzzle. It does not, it starts to fall as soon as it leaves the barrel.
If the barrel is pointed upward at any angle the bullet will rise in relation to the earth, but it will never rise above the angle of the bore. For example if the barrel is pointed up at a 10 degree angle. The bullet would never rise above 10 degrees in relation to the earth. Even if we raise the muzzle, the bullet still begins to fall as soon as it leaves the muzzle, in relation to the bore. It would be rising, in relation to the earth however.
If the barrel is pointed upward at any angle the bullet will rise in relation to the earth, but it will never rise above the angle of the bore. For example if the barrel is pointed up at a 10 degree angle. The bullet would never rise above 10 degrees in relation to the earth. Even if we raise the muzzle, the bullet still begins to fall as soon as it leaves the muzzle, in relation to the bore. It would be rising, in relation to the earth however.