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Posted: 8/8/2005 8:47:16 PM EDT
Hi, folks.

Sorry if this has been asked before, but I'm not finding anything in my searches.  How is a bullet's trajectory different if shot from an extreme downward angle?  (I live on the 30th floor, so I've wondered about this when I daydream but I'm physics challenged.)
Link Posted: 8/8/2005 8:56:58 PM EDT
[#1]
Im going to give this question a whirl, basically when you shoot at a downward angle, you are using the force of gravity to your advantage creating less drop in the bullet since it is already going downward. As opposed to some1 shooting perfectly horizontal with the ground, the bullet would gradually drop until it hit the earth making more of an arc than a straight line. A bullet that is already being shot downward doesnt have to arc becuase it is already heading toward the force of gravity, therefore making the bullets path more of a straight line than an arc. So it would seem that if you shoot at a downward angle, you would have better accuracy becuase there is less drop in the bullet over distance.
Link Posted: 8/8/2005 9:05:48 PM EDT
[#2]
In other words your shots would hit high. This is most obvious when bowhunting from an elevated stand.
Link Posted: 8/8/2005 9:16:22 PM EDT
[#3]
Look at it this way...actual drop would be same as if you were making the same shot on HORIZONTAL DISTANCE ONLY.

For example, you are 30 floors up at the corner of 1st and avenue A.  The target is at 4th and avenue E.  The horizontal distance would then be 5 blocks in horizontal distance or 500 yards (based on a pseudo-standard of 300 foot long blocks).  The actual flight path would be 510 yards, give or take a little.  You would not need to correct for most shots.

Learn your trig.  Apply your trig.  Learn your physics.
Link Posted: 8/8/2005 10:36:43 PM EDT
[#4]
www.ballisticards.com/slopedoper.htm


For angle shots, the effective distance is less than for a flat shot.  Get your line of sight range, measure the angle, multiply the range by the conversion factor, and you have the effective range.  


For a 500 yard shot at a 30 degree angle, the effective range (and the range you dial in on your scope) is 435 yards.  
Link Posted: 8/8/2005 11:46:40 PM EDT
[#5]
I think all dialogue this means it will not drop as much as what distance alone would suggest.  So hold relatively low or you will shoot too high.

Rick
Link Posted: 8/9/2005 12:41:12 AM EDT
[#6]
Link Posted: 8/9/2005 8:55:21 AM EDT
[#7]
Cool, thanks for the explanations guys.  Sometimes, it takes me a little bit to get up to speed in this stuff.  
Link Posted: 8/9/2005 9:57:25 AM EDT
[#8]
Angle fire correction:  the angle of the line of sight from the gun to the target.  This slant range is derived from the cosine of the angle multiplied by range.  Example:  if the laser range finder indicates the target is 600 yards and the gun is 30 degrees higher than the target (cosine .87 x 600) , then the corrected range is 522 yards.  The average correction is minus 2 MOA (minute of angle).  Without Angle Fire correction, the bullet impact will be 12 inches high.  BTW, the same holds true if you are shooting up.
Link Posted: 8/9/2005 10:12:34 AM EDT
[#9]
You should not be firing from the 30th floor down to street level.

You should move to floors 5-10 for that.
Link Posted: 8/9/2005 11:12:43 AM EDT
[#10]

Quoted:
Angle fire correction:  the angle of the line of sight from the gun to the target.  This slant range is derived from the cosine of the angle multiplied by range.  Example:  if the laser range finder indicates the target is 600 yards and the gun is 30 degrees higher than the target (cosine .87 x 600) , then the corrected range is 522 yards.  The average correction is minus 2 MOA (minute of angle).  Without Angle Fire correction, the bullet impact will be 12 inches high.  BTW, the same holds true if you are shooting up.



Interesting.  Thanks for that info.  
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