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Sight Settings and Adjustments
Clicking the Sight Settings page button will open this page displaying the following information:
After the ballistics and trajectory have been calculated, a Point-Blank-Range-Zero may be calculated from this page. Point-Blank-Range is a concept useful in hunting situations where sight adjustments are not practical..
The point blank range may be defined as the maximum distance a shooter can sight directly on the target or game animal and be assured of a bullet strike within the vital zone of that target or animal.
At distances closer than the point blank range, the bullet will not rise above one half the diameter of the vital zone above the line of sight or fall below the line of sight more than one half of the diameter of the vital zone.
To calculate the point blank range, enter a value that is one half of the diameter of the desired vital zone into the first entry field and then select the "Calculate the Point Blank Range" button.
The one half diameter of the vital zone entry must be at least equal to or more than the front sight or scope height.
After the calculations, the distance at which the bullet first crosses the line of sight will be indicated in the L.O.S. window.
The distance to the point where the bullet is at the highest point in the trajectory will be shown in the Maximum Height window
The range at which the sights should be zeroed in order to facilitate this procedure is shown in the Point-Blank-Range window.
The range at which the bullet will be at one half the radius of the vital zone below the line of sight is shown in the Maximum-Point-Blank-Range window.
Different values may be repeatedly entered into the Maximum Height Field and calculated without having to re-calculate the initial trajectory.
When values are calculated and displayed in the various range windows above, those same values are also entered into the Initial Data Optional Range Fields on the Data Entry Page.
If the selected sight configuration is a " fixed" sight, then no sight adjustment window will be opened.
The Maximum Distance Above the Line of Sight value must be equal to or more than the front sight height for the calculations to take place. After the "Calc Point Blank Range" is clicked the various Point Blank Ranges will be displayed in the Range Fields. These Ranges will also be entered into the Initial Data Optional Non Incremental Ranges Fields and calculated to display the bullet path, minutes-of-angle and sight adjustment graduations used to zero at each range.
A 'Scope sight selection shows a window indicating the number of clicks or dial graduations to change the zero to any indicated range.
A Vernier Sights selection cause two windows to appear, as shown above, with the associated readings and adjustments.
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