Line of Sight and Trajectory

Discussion in 'The Basics, Starting Out' started by phillietimothy, Nov 16, 2011.

  1. phillietimothy

    phillietimothy Well-Known Member

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    Hello all, I have a question about line of sight as it relates to trajectory. If a round drops 30" at 400 yards, wouldn't the center of the target have to be at least 30" above the line of sight? I understand that the drop from the axis of the bore will be more because the barrel is angled slightly upward. It is my understanding that the line of sight is a straight line from the sight to the target. I guess what I am asking is - how can one shoot at a distance if the target is not sufficiently high? On a completely flat surface, wouldn't one be limited in distance by the drop from line of sight at a specific distance? Please help, this is driving me crazy.
     
  2. justgoto

    justgoto Well-Known Member

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    [deleted wrong statement]


    I should have stopped reading your gibberish, it screwed me all up.

    The target is exactly the same height as the line of sight.

    The bore axis is the only thing aligned above the line of sight.

    That is the part that is backwards; unless there is a ceiling above that surface, there is no problems whatsoever.
     
    Last edited: Nov 16, 2011

  3. phillietimothy

    phillietimothy Well-Known Member

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    Thank you for your reply. I don't understand where drop is measured from. The gibberish comment is uncalled for.

    Tim
     
    Last edited: Nov 16, 2011
  4. Scot E

    Scot E Well-Known Member

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    Having a bit of trouble understanding what you are asking. Maybe this will help.

    figure1x.jpg
     
  5. phillietimothy

    phillietimothy Well-Known Member

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    Scot E,

    That helps immensely. I was having a lot of difficulty phrasing the question. When I see 30" drop at 400 yards, according to the diagram, the drop is from the trajectory line. Is this correct, thanks again.

    Tim
     
  6. Browninglover1

    Browninglover1 Well-Known Member

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    What that drop means is that if your gun was sighted in for 100 yards and you shoot at your 400 yard target you would miss low by 30". The diagram that Scott posted shows you that you can compensate for this drop by adjusting your scope so that your bullet will hit where your line of sight is pointing at a given range.

    Another way you could look at it: hold 30" above where you want to hit at 400 yards and the bullet will follow the trajectory as shown in his diagram and still hit where you wanted it to hit even though according to your line of sight you were aiming 30" high.

    All this trajectory talk could be negated if we shot projectiles that weren't affected by gravity. Ex. Laser gun.
     
  7. phillietimothy

    phillietimothy Well-Known Member

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    Browninglover1,

    Thank you for your reply. I understand what you are saying.

    Tim
     
  8. Bravo 4

    Bravo 4 Well-Known Member

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    +1
    This also shows you the maximum ordinance, or the highest point of the trajectory (marked in the pic as vertical drop).