I will explain how to use an MRAD Reticle to your advantage. Using an MRAD reticle will enable you to measure a distant object, find the range of a distant object and to adjust accurately for bullet drop or wind drift. First some basic information to get you familiar with your MRAD Reticle…
MRAD UNIT OF MEASURE = MILLIRADIAN
This is the unit of measure that tells you how far you have gone around a circle. A milliradian is 1/1000th of a radian.
(To visualize this, imagine you are eating just the crust of a pie. Each tiny nibble being a milliradian and each full pie slice being a radian.) In a full circle there are 6,280 milliradians, or 6.28 radians. (Milliradians are the amount of angle around a circle similar to a sliver of pie.)
The MRAD RETICLE
The MRAD reticle features a crosshair formed by a vertical and a horizontal line intersecting one another, each with either “mil-dots” or subtension lines along both the vertical and horizontal planes. The measurement from the center of one mil-dot to the center of the next mil-dot is 1 milliradian and on the other, from the larger subtension line to the next larger subtension line is 1 mil. (The smaller subtension lines being .5 of a mil.)
In order to use a MRAD reticle properly you need to know from the manufacturer or dealer if your reticle is in the first focal plane (FFP) or the second focal plane (SFP) if you have a variable power scope. If it is in the FFP then the MRAD measurement remains accurate at each power of magnification. If it is in the SFP then your scope must be used generally at the highest level of magnification to retain accuracy.
Finding RANGE Using Your MRAD Reticle
To find range using your MRAD reticle you will use a basic formula. In the USA most shooters use yards as the most common unit of measurement. To find the yards to the target you need to know the height of the target in inches. Lets say the target is 36” tall. Multiply 36”x 27.778 then divide by the mil size (milliradians) of the object as seen through the reticle. The result is the number of yards to the target.
(Target size inches x 27.778 /mil size = yards to target)
For Meters (target size in centimeters x 10/mil size = meters to target)
Most hunters use laser range finders these days and don’t have need of this knowledge any longer.
Finding SIZE Using Your MRAD Reticle
You may wish to gauge the size of the head gear of your prospective elk, deer, caribou or ram before taking a shot. You can do this accurately using your MRAD reticle! You begin by checking the range. You check and we’ll say your target is at 250 yards. Then you measure the size of the width (or height, where ever your interest lies) of antlers in mils through your reticle. You employ the formula as follows: Distance in yards multiplied by mil size then divide 27.778 = The result will be the head gear (or anything you wish to measure i.e.; a man, an opening in between objects etc.) size in inches.
For inches (250 yards x mil size/27.778=size in inches).
For Centimeters (distance in meters x mil size/10=size in centimeters.
Mils in INCHES at VARIOUS YARDS
This chart gives the number of inches for 1 mil at varied distances in yards: Again, 1 mil is the distance from the center of one mil-dot to the center of the next mil-dot or one large subtension line to the next large subtension line.
1 MIL In Inches
1 MIL IN INCHES
Using MILLIRADIANS for Bullet drop
To use Mil-dots or subtension lines effectively you will be required to know the ballistics for the ammunition you are utilizing. It is essential to know how far your bullet will drop while traveling a particular distance. Most manufactures commonly post this info on the internet. The formula to use is as follows:
Bullet drop divided by 1 mil size for that distance=mils needed for adjustment. Hornady states a drop of 1271.7 cm at 500 meters and suggests a 25.5 mil compensation. Therefore, the formula:
1271.7cm/50 cm=25.5 mils.
MIL-DOT/SUBTENSION LINE HOLDS
Mil-dot and subtension line holds aid in Kentucky windage and bullet drop scenarios as well. Assume you shoot at a distant target and see through your scope that the point of impact was 1 mil below your target. Not wishing to adjust your turret, you can simply raise your cross hairs one mil higher on the target to compensate. This also applies horizontally for wind drift and for leading moving targets. Allowing you to compensate quickly and accurately for quick follow up shots.
SIMPLE TURRET ADJUSTMENTS
On 0.1 mil or 1/10th scopes you can fine tune using 10 clicks per 1 mil of adjustment. For instance, after your shot, your hunting guide watching through a spotting scope says, “drop 2 mils” you will turn the turret down 20 clicks. At a 100 yards that will bring you down approximately 7.2” (using the chart above showing distance and approx mil in inches). Having a unified unit of measurement between spotters and shooters increases accuracy at long ranges and in group scenarios.
I hope this brief explanation improved your knowledge of how to use a MRAD Reticle and will increase your accuracy in the field while on that dream hunt and at home at the target range.