Quantcast
  1. Sign up now and join over 35,000 northwest gun owners. It's quick, easy, and 100% free!

Shooting up and down hill

Discussion in 'Rifle Discussion' started by Djac315, Nov 7, 2009.

  1. Djac315

    Djac315 eugene Member

    Messages:
    47
    Likes Received:
    2
    I am trying to get the truth about shooting up and down hill. I have heard that it is the same as shooting on a flat plane but I have also heard that you need to compensate for it. Any input would be great thanks.
     
  2. CrossHairs

    CrossHairs Tigard Active Member

    Messages:
    256
    Likes Received:
    38
    If you are shooting up or down, you actually only adjust for the distance between you and the object along the horizontal plane because that's the distance that gravity is having an effect on your projectile.

    Think of a 3, 4, 5 triangle(hopefully you remember your math classes), with the longest side (5 units) being the distance directly to your target(point to point). The shortest side (3 units) being the height above the ground and the mid dimension (the 4 units) being the distance along the ground from you to below where the object is sitting. In this case, the actual distance for adjustment would be for 4 units.....not the total distance to the object!

    So, if you had sighted in at 5 units, and the object is now at four units, your going to have to adjust down accordingly.

    So in real terms.....you are 50 yards from your target, but the target is 30 yards off the ground. Your gun is sighted in for 50 yards, therefore, you will have to shoot slightly lower or risk your shot going over the top.....!

    I found some cool resources on the web once, but I cna't seem to locate them. a quick glance left me with this.


    http://www.snipertools.com/article.htm
     
  3. Inspector

    Inspector Washington State Member

    Messages:
    120
    Likes Received:
    17
    Keep in mind that the same effect applies whether shooting up or downhill. In both cases your bullet will hit high. This boggled my mind. I couldn't get my brain around it. I finally came to understand it differently in my own mind by just looking at it as an effect of gravity. The lightbulb came on when I quit trying to understand all the drawings on the internet. I simply ran across the following statement:

    "When shooting up hill or down hill the force of gravity is not fully exerted on the bullet since the bullet is not flying perpendicular to the earths surface. Therefore the gravity force when shooting up hill or down hill is less than the force exerted on the bullet when shooting flat or perpendicular to the earth. So, the bullet will NOT drop as much since the force is less.... and you would not dial as much MOA as you normally would or hold lower that you normally would at that distance."
     
  4. speelyei

    speelyei Willamette Valley Active Member

    Messages:
    498
    Likes Received:
    29
    chuck hawks answers all:

     
  5. Dan-Dee Sales Inc

    Dan-Dee Sales Inc Sweet Home, Oregon, United States Active Member

    Messages:
    606
    Likes Received:
    56
    They do make rangefinders that account for the angle. Just look for one that has (ARC) on the label. (Angle Range Compensation). Bushnell has one for $259.00