Choosing And Using Modern ReticlesBy John Barsness
©Copyright 2010, The Varmint Hunters Association, Inc.
Reticles with multiple aiming points were occasionally used long before we ever heard of the Rapid-Z, Ballistic-Plex, B&C, and all their kin. The difference, however, is that back in ancient times, BLRF (Before Laser RangeFinders) the use of different aiming points amounted to guessing, because unless we were shooting on a formal target range, we didn’t really know the distance. We could “eyeball” it, but human eyeballs are too close together to accurately estimate distance much beyond how far a reasonably healthy man can throw a baseball.
While Bushnell’s DOA reticle is actually designed for deer hunting, it also works very well for coyote shooting.
Once laser rangefinders became affordable, however, reticles rapidly sprouted extra dots and crosshairs. This multiplicity of choices naturally brought about not just commercial competition but debates about which reticle works best. This debate is muddled by the mil-dot type of reticle that existed even before laser rangefinders became common.
The mil-dot reticle was developed by the military as both a multi-point aiming system and as a ranging system. (In fact, some shooters think “mil” is short for military, when it’s actually short for milliradian, a unit of measurement involving the arc of a circle.) Dots that are spaced a precise, known distance apart can be used as fairly precise rangefinders on targets of a known size, such as the average adult human. This can even be done with a standard plex-type reticle, a system I still use on occasion when hunting big game, partly because a laser rangefinder doesn’t always work, and partly because sometimes a nervous deer doesn’t provide enough time for a laser reading.
The Burris Ballistic Plex is a very simple dot reticle that works very well on rimfires and other short-to-medium range rifles.
Many mil-dot type reticles, however, aren’t ideal for a lot of varmint shooting. The dots are usually arrayed along one horizontal and one vertical crosshair. This doesn’t provide a prairie dog shooter much help when holding off for the wind at longer ranges, because there are no reference points on either side of the vertical crosshair.
The VARMINT HUNTER Magazine, a 208-page publication put together for shooters by shooters. The Varmint Hunters Association, Inc. hosts several 600-yard IBS matches, a coyote calling contest, and an annual Jamboree in Fort Pierre, SD. The Jamboree is a week-long shooting event known as "a summer camp for shooters".This weakness in the basic milt-dot type reticle eventually led to the “Christmas tree” reticle, with multiple crosshairs below the primary intersection of crosshairs. The lower crosshairs are longer because at longer ranges bullets drift more in the wind, and as a result the reticle’s profile looks something like a bare conifer. A Christmas tree reticle is useful because at longer ranges we can “slide” one of the lower reticles along the target to compensate for wind drift, instead of just holding a dot somewhere off to the side.
All modern multi-point reticles are some variation of mil-dot and Christmas tree, and often combine the two. Before delving deeper into specific reticles, however, let’s look at some basic optical concepts.
One principle many shooters still don’t understand is that with most scopes any reticle is going to be valid only when the scope is set on a particular magnification. This is because more than 99 percent of variable scopes sold today have the reticle in the second focal plane (SFP), behind the power-change mechanism.
This means that when the magnification is changed, the apparent size of the reticle changes in relationship to the target. Thus our carefully worked-out aiming points for 100, 200, 300, etc. yards are suddenly invalid. This doesn’t matter to prairie dog shooters as much as it does to coyote hunters, because prairie dog shooters often have their scope cranked all the way up, but even PD shooters will sometimes adjust their scope because of mirage conditions.
Many shooters also don’t fully understand that even when their scopes are kept on the same magnification, the various aiming points still won’t necessarily match the trajectory of their rifle’s load. This is partly because so many manufacturers put a handy table in the box with their scopes, detailing exactly how our particular load (or the closest approximation) will match up with the reticle at 100, 200, 300, etc. yards.
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