Using a range card
The range card provides ready access to some of the most frequently required information for placing measured shots at distance. The first and largest variable to account for in all ballistic solutions is bullet drop, or the effect of gravity on a bullet in flight over time. Auto-populated for your unique combination of rifle and optic in hand, the range card dedicates a majority of its data to accurately accommodating this first variable in a ballistic solution.
Using a range card
The coloured columns under the range card’s “Bullet Drop” section display different sets of adjustments to accommodate the effects of temperature on bullet drop. As temperature affects both muzzle velocity and air resistance, the differences between cold and warm climates can have a significant effect on how far a bullet will fall due to gravity at any given range. Be sure to have a rough estimate of the temperature in hand to help decide which temperature column to read.
With an appropriate temperature column picked out, all of the below values will display how far your bullet will drop for the given “Target Range”, found on the far left side of the sheet. These drop values are measured in milliradians, or MRAD. For example, a value of “-4.5” (reading the 15°C temperature column at a distance of 500m) describes that your bullet will fall 4.5 milliradians below your crosshairs at that distance. To counteract that negative drop value, we need to either hold the crosshairs 4.5 MRADs above the target, or dial our scope up 4.5 MRADs to bring the bullet impact back up to our crosshair level.
Advanced considerations
In a similar fashion, the range card also provides information for use with wind accommodation, engaging moving targets, and for calculations requiring general equipment information. This data, however, is seldom required in the opening marksmanship roles where simplicity encourages speed, and speed is our most valuable asset.
At the highest level of marksmanship roles, it should be noted that the populated BDA information is limited to temperature and equipment considerations only. Displayed drop values do not account for changes in altitude, pressure or humidity variables, as default Arma values are assumed. This under extreme conditions may compromise all drop, wind and moving target information, requiring manual data collection or calculation.
