VIDEO: "Best Distance to Zero a Hunting Rifle"

 

VIDEO: "Best Distance to Zero a Hunting Rifle"--Backfire (13 min.). 

The author explains why he uses a 100 yard zero.

    For as long as I can remember, the standard advice to hunters using a scoped rifle was to sight the rifle at its maximum point blank range--"the distance over which a shooter can hold his sights dead on the center of the target and hit it"--so that there was no need to do on the fly adjustments in the field.  Or, as one author describes it: "The MPBR method is a compromise between precision shooting and getting off a quick shot, so it is not perfect, but it is a method that will help put bullets in the kill zone if you understand the method and use it within specified distances." If done correctly, you can put the crosshairs of the scope over the vitals of a deer or elk and be able to strike within the vitals, whether slightly high or slightly low from your actual point of aim, out to 250 or 300 yards. 

    The MPBR is going to vary according to different calibers, bullets and velocities, but for common hunting calibers, it is probably going to be about 250 yards if hunting deer (figuring about a 10 inch wide vital zone, allowing you to hit up to 5-inches above and below the point of aim and still strike the vitals). The normal process of determining MPBR involves verifying shots at various ranges, but because many hunters did not have access to target ranges allowing shots beyond 100 yards (or a chronograph), it became common advice to sight the the scope so you struck the target 2 to 3 inches above the point of aim at 100 yards. Today, with ballistic calculators, you can calculate your offset at 100 yards much more precisely. (Here is the link to Hornady's online ballistic calculator. A tip: sight height over the bore is pretty important. The default on this calculator is 1.5 inches, but that would be for a scoped bolt action rifle and obviously depends on your particular set-up. Other types of rifles will vary. The height over bore for an AR, for instance, using a standard height mount is in the range of 2.5 to 2.75 inches or thereabouts. It pays to measure it).

    But scopes have changed. Exposed turrets have made it much easier to adjust a scope on the fly. Zero stops make it easier to bring it back to its original zero. Reticles that incorporate bullet drop compensators or other means of adjusting your point of aim are now very common. A few companies (e.g., Leupold) even offer custom turret caps marked with the adjustments needed for specific distances for your rifle and load. 

    And that is where the author of the video above seems to be coming from. He recommends a 100 yard zero because it is more precise (i.e., less subject to the bullet being driven an unknown distance off target due to wind) than trying to sight in the rifle at 200 yards, for instance; and then adds that in the field you can quickly adjust your scope up the number of clicks necessary for taking a shot at a longer distance.

    I suspect that this is one of those issues where the proper answer is "it depends." If you are hunting in dense woodland where it is rare to take a shot over 100 or 150 yards, a 100-yard zero might be all you need. Someone hunting in open country or where the trees are not very close might see a deer or elk ambling along and have time to adjust his scope before the animal disappeared behind a copse or some brush. It might be different if you are in an area where you have longer shots, but because there is more cover, you have less time to take the shot. And, obviously, the on-the-fly adjustment isn't going to work for someone that has to unscrew caps and use a coin or screw driver to adjust their scope.