The Shepherd DRS (Dual Reticle System) is a fast, easy approach to passive range finding. The idea was conceptualized over 35 years ago and is still as effective and simple as it was in the first prototype.
For quick range finding there are a series of circles in the first focal plane reticle that are a based on a target size at distances. Reticles are available in 9”, 18”, and 24” stadia circle. As long as you know the approximate size of the target you can use the circles to find its range. Below are some common target sizes.
COMMON TARGET SIZES: DEER 18" FROM SHOULDER TO BRISKET ELK AND LARGE GAME 24” CHEST AREA - 18" FROM NOSE TO BACK OF HEAD (OR USE THE CIRCLE THAT FILLS 3/4 OF ITS BODY MASS) COYOTE 9” FOR CHEST AREA - 18" STANDING FROM GROUND TO TOP OF BACK PRAIRIE DOG AN ADULT IS 9" LONG OR USE HALF OF AN 18” CIRCLE MILITARY SILHOUETTE TARGET IS 18” TO 20” ACROSS THE SHOULDERS
As an example, let’s say there is a deer standing 400 yards away from a hunter. Using the series of decreasingly smaller circles, match the chest area of the deer in the circle that fits. The number beside that circle is the range, in this case 4. By using the center of the circles, the scope is automatically compensating for the bullet drop at that range. Just Fit and Fire – it’s that simple!
In addition to ranging the animals of known sizes above the shooter can also use the riflescope to range other objects. The shooter can use the scope to tell the size of a rack for instance before taking the shot. If you have a deer that fits the 600-yard circle and his rack covers 6 MOA spaces in the scope you simply multiply [6 (for the yards) x 6 (for the moa spaces)] and get the number 36. Therefore, the buck has a 36 inch rack.
The calculation also works in the other direction. Say the shooter has a known target that is 30” and that target covers 6 MOA spaces. If you divide the target size of 30” by the 6 MOA you will get 5. Therefore that target is at 500 yards. The shooter can then put the 500 yard circle on him and fire. The system has been designed with the range finding circles set on the same focal plane as the target. This means that as you zoom in and out the circles increase and decrease proportionally. They are always accurate! No more zooming to one power to find the range and zooming to another to shoot. You are always on with the Shepherd DRS.