CNYCacher
Member
Very simple explanation: They are not shooting with the muzzle level. It is actually pointed up slightly to compensate for bullet drop at 150 yards. You actually shoot it upwards.
Gun Myth
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Very simple explanation: They are not shooting with the muzzle level. It is actually pointed up slightly to compensate for bullet drop at 150 yards. You actually shoot it upwards.
PlayboyPenguin
member
I am sure someone has said this already but the only thing I can think of that would alter this is if the bullet has flaw that might cause air to move more quickly over the top side of the bullet therefore reducing the pressure above the bullet causing it to rise as it went forward.
TexasRifleman
Moderator Emeritus
Sounds simple doesn't it?
But I hear and read (some on here even) that they just KNOW for a fact their bullet climbs
Wesker
Terminal velocity makes things fall at different velocities in air due to wind resistance. Dropping them on the moon took terminal velocity out of the equasion so that acceleration due to gravity was the only factor. A feather will fall slower on earth than a hammer due to its terminal velocity. But 2 objects of equal terminal velocity will fall at the same rate on earth (one bullet dropped, one fired).
Terminal velocity makes things fall at different velocities in air due to wind resistance. Dropping them on the moon took terminal velocity out of the equasion so that acceleration due to gravity was the only factor. A feather will fall slower on earth than a hammer due to its terminal velocity. But 2 objects of equal terminal velocity will fall at the same rate on earth (one bullet dropped, one fired).
CNYCacher
Member
If you want to really bend some minds:
When shooting downhill, do you hold high or hold low?
Why?
I am voting for "aim low", since the direction of gravity is less down and more forward, getting the bullet there faster, and pulling it less perpendicular to flight.
When shooting downhill, do you hold high or hold low?
Why?
I am voting for "aim low", since the direction of gravity is less down and more forward, getting the bullet there faster, and pulling it less perpendicular to flight.
akulahawk
Member
Hold High OR Hold Low...
You're almost right. When you're shooting at an angle, high OR low, you effectively shorten the distance horizontally between your muzzle and your target. Basically think of it as a right angle triangle. You're at one angle (top or bottom) depending upon uphill or downhill. The line directly down (or up) is gravity. Its length depends upon vertical displacement between you and the target. That end is the right angle where horizontal distance comes into play. Your 225 yard (up hill or downhill) shot may actually be an 180 yard horizontal distance. You'd hold for the 180 yards. In otherwords, with such a shot, if you figured and held for 225 yards, the shot would go high.
Physics and Trig definitely DO apply in the real world.
You're almost right. When you're shooting at an angle, high OR low, you effectively shorten the distance horizontally between your muzzle and your target. Basically think of it as a right angle triangle. You're at one angle (top or bottom) depending upon uphill or downhill. The line directly down (or up) is gravity. Its length depends upon vertical displacement between you and the target. That end is the right angle where horizontal distance comes into play. Your 225 yard (up hill or downhill) shot may actually be an 180 yard horizontal distance. You'd hold for the 180 yards. In otherwords, with such a shot, if you figured and held for 225 yards, the shot would go high.
Physics and Trig definitely DO apply in the real world.
Sorry, didn't see the "why?" Akulahawk answered it well, but here's a good read.
http://www.loadammo.com/Topics/April04.htm
http://www.loadammo.com/Topics/April04.htm
Some of the confusion might come from the fact that, if using a scoped rifle, for example, the line of sight is above the line of bore. Thus, even if a bullet didn't fall due to gravity, one would still have to point the bore slightly above level to have the bullet hit at the point of aim (assuming the line of sight was perfectly level). The fact that a bullet *does* fall with gravity means that the line of bore must be inclined even more to hit the target.
Consider this, using .308 as an example, with the bore being perfectly level. The average velocity of the bullet between the muzzle and a target 100 yards away is about 2600 fps. The time to target will be 0.1154 seconds. During that little more than one tenth of a second, the bullet will drop about 2.5 inches due to gravity.
Look how quickly drop increases at long ranges. The average velocity of the bullet to a target 500 yards away will be 2200 fps. (Please note, this is the average velocity to 500 yds, not the velocity AT 500 yds.) The bullet will take 0.68 seconds to reach that range. During that time it will fall about 90 inches. (Okay, the actual distanced dropped will be a *little* less because these calculations do not take vertical air resistance into account. But, you get the idea)
Here's a good website for *basic* ballistics information.
http://members.aye.net/~bspen/ballistics.html
K
Consider this, using .308 as an example, with the bore being perfectly level. The average velocity of the bullet between the muzzle and a target 100 yards away is about 2600 fps. The time to target will be 0.1154 seconds. During that little more than one tenth of a second, the bullet will drop about 2.5 inches due to gravity.
Look how quickly drop increases at long ranges. The average velocity of the bullet to a target 500 yards away will be 2200 fps. (Please note, this is the average velocity to 500 yds, not the velocity AT 500 yds.) The bullet will take 0.68 seconds to reach that range. During that time it will fall about 90 inches. (Okay, the actual distanced dropped will be a *little* less because these calculations do not take vertical air resistance into account. But, you get the idea)
Here's a good website for *basic* ballistics information.
http://members.aye.net/~bspen/ballistics.html
K
White_Wolf
member
Ballistics is based on the concept that a bullet in motion will hit the ground at the same time as the one with forward energy. So the myth is a fact. If not, the entire science of ballistics would have to be rewritten.
Also, aim high or low?
If you were shooting uphill, while standing upside down, would you aim high or low... have fun
Also, aim high or low?
If you were shooting uphill, while standing upside down, would you aim high or low... have fun
Skywarp
member
Vectors!
Its true. Bullets do not generate lift so there isno counteractive force to resist the vertical acceleration of gravity.
Its true. Bullets do not generate lift so there isno counteractive force to resist the vertical acceleration of gravity.
SDM
Member
I know this deals with the wording but...if you drop the one bullet when you "shoot" the gun, the dropped bullet will hit first. The fired bullet had to spend some (very little though) time travelling the length of the barrel before it was "dropped".
Isnt the bullet "climb" an actual phenomenon...just perhaps attributed to the wrong thing, such as the actual bullet moving rather than what the sights are really pointing at?
Assuming a perfectly flat trajectory:
If you're sighted to 100 yards, but fire at a target closer than 100 yards, the bullet will strike below the point of aim. If you're sighted at the same distance but shoot beyond 100 yards, the bullet will strike above the point of aim.
Assuming a perfectly flat trajectory:
If you're sighted to 100 yards, but fire at a target closer than 100 yards, the bullet will strike below the point of aim. If you're sighted at the same distance but shoot beyond 100 yards, the bullet will strike above the point of aim.
Eleven Mike
Member
KenRocks, in one sense you're right. The bullet climbs in relation to the line of sight. But it's falling toward the earth the whole time.
spankaveli
Member
It's not a myth if it's true.
BobTheTomato
Member
In response to the initial question everyone here seems to be ignoring curvature of the earth. Sorry that is an Engineer reply
Sorry that is an Engineer replyAnd so, the point of the lesson is lost on you. That point being that the effects that you're told to ignore are acutally VERY significant and do indeed change the ideal physics that one might find in space.another person said:
Hopefully the lesson should impress upon you the difficulty of predicting a ballistic path. It should impress upon you that the variables are too numerous and unpredictable to positively calculate a projectile's flight path. It should impress upon you that the more powerful the munition the further the projectile will go and the greater the difficulty in putting it EXACTLY where you want it. It should impress upon you the truly remarkable nature and accuracy, therefore, of the way our military's weapons are targeted in a time of war.
You've been taught lesson number one about ballistics. There's considerably more to it than that.
s
Taurus92 in KyleTX
Member
Back to Hazzard's comment on wind resistance related to the original question... I think the timing of each bullet's fall (one from the barrel, one dropped from the hand) depends on how they fall.
Disclaimer: I don't reload, so don't know the real measurements or weight distribution characteristics of a bullet.
I would suspect the spinning bullet from the barrel would present more surface area to the vertical vector, generating more wind resistance, and falling at a slower terminal velocity.
Similarly, I would expect a bullet that is dropped to rotate on end due to weight distribution, thus presenting less surface area (and possibly a more aerodynamic shape) to the vertical vector. Thus, the dropped bullet would have higher terminal velocity, striking the ground sooner than the fired bullet.
Am I missing something? It's been a while since I sat in a physics class, so I may be off on what factors impact terminal velocity.
Disclaimer: I don't reload, so don't know the real measurements or weight distribution characteristics of a bullet.
I would suspect the spinning bullet from the barrel would present more surface area to the vertical vector, generating more wind resistance, and falling at a slower terminal velocity.
Similarly, I would expect a bullet that is dropped to rotate on end due to weight distribution, thus presenting less surface area (and possibly a more aerodynamic shape) to the vertical vector. Thus, the dropped bullet would have higher terminal velocity, striking the ground sooner than the fired bullet.
Am I missing something? It's been a while since I sat in a physics class, so I may be off on what factors impact terminal velocity.
JesseL
Member
There is a small caveat to this subject:
It assumes that the earth is flat
If you fire the bullet fast enough (and neglect aerodynamic resistance, and you don't have any backstop) it will go into orbit at the altitude it was fired from.
It assumes that the earth is flat
If you fire the bullet fast enough (and neglect aerodynamic resistance, and you don't have any backstop) it will go into orbit at the altitude it was fired from.
BobTheTomato
Member
Well you would need to move the gun once it is fired to prevent it from hitting the back of it.
RNB65
Member
True. Gravity is gravity. As long as the bullet starts on a path that is parallel to the ground, gravity will pull it down at the same rate as the dropped gun.
sacp81170a
Member
The one factor that can throw a kink into this scenario is the curvature of the earth. Granted, we're talking about firing a pistol round from 4 feet above the ground, but given more altitude and distance the curvature of the earth becomes a factor. The calculations for long range artillery account for this among other factors. Otherwise, not a myth. True, given a flat surface.
usp9
Member
To be perfectly accurate the comparison must be made by equating the moment bullet A is dropped Vs. the moment bullet B leaves the barrel. Then both bullets would strike the earth at the exact same moment on a flat plane. The fired bullet would travel the 4 feet vertical and about 150 feet horizontally.
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