We’ve all been there…
But this makes it easy!
Much has been written on the ideal distance to zero a hunting rifle. There is no best sight-in range for everyone, because the range at which hunters expect to shoot their quarry differs considerably. For example, if you hunt exclusively from a ridge top that overlooks a food source that is 150 yards away, you should zero for that distance. But if you hunt various terrain that offers both short- and long-range shots, here’s a technique that’ll allow you to hold the crosshairs on the vitals of deer-sized game or larger and keep your bullet inside the vital zone out to 280 yards, give or take a few yards depending on your caliber. It’s called point-blank range, and to maximize it you should alter your sight-in range for a particular load, rather than letting your traditional sight-in distance dictate your rifle’s zero.
Point blank range defined is the range of distances at which you can hold your rifle on the bullseye and never fall in or out of your target’s kill zone. The point blank range for a deer, for example, is generally regarded as six inches. In other words, if you hold dead center on the vitals, your bullet can be 3 inches high or 3 inches low before it slips out of the vital zone. An elk’s vital zone is larger of course—we’ll say 8 inches. But I like to stay with the 6-inch rule of thumb because is allows for some shooter error, an occurrence that you’d be naive to assume doesn’t happen while in field positions shooting at wild game.
So many hunters zero their rifles at 100 yards that it’s almost become standard practice. But the following examples will illustrate why that’s not a great zero for a rifleman who wishes to be able to take shots quickly, without calculating, from point blank to nearly 300 yards.
As an example, let’s use a very common hunting round, a .270 Win., loaded by Remington with a 130-grain Premier Accutip boattail bullet that has a .447 Ballistic Coefficient (BC). It’s got a muzzle velocity of 3,060 fps. Ballistically, it falls in line with a whole class of moderately fast calibers. The scope (line of sight) is mounted 1.5 inches over the middle of the bore. Zeroed at 100 yards, the bullet will impact .76 inches low at 25 yards (this is just fine for hunters), and will be 2.98 inches low at 203 yards. But after 203 yards it falls below the 6-inch vital zone. (That’s missing the 6-inch circle, 3 inches below the center, or point of aim.) At 250 yards, it will impact 6 inches below the point of aim, (three inches out of the vital zone.) So, with a 100-yard zero, a hunter can simply aim at a buck and expect to hit it in the vitals anywhere from 0 to 203 yards.
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