Deer Hunting Rifles: Sighting In

Today’s deer hunting rifles are the epitome
of the gun maker’s art. In fact, teamed with the
right ammo, they’ll often make up for pilot error.
Still and all, a properly sighted-in rifle helps
assure a clean, one-shot kill.

It happens every year, just before the season. Would-Be-Nimrods show up at the range with their deer hunting rifles to sight them in. But more times than not, they’re not quite sure what they’re doing.

In a typical scenario, at least two, and often three, buddies show up to help each other with the task. The first shooter gets down on the bench, supporting the rifle with his elbows. He fires one shot, and the other guy, watching through binoculars, says something like, “an inch low and two inches to the left.” The shooter than fiddles with both scope adjustments, and fires one shot again.

“Now you’re a little high, and still an inch to the left,” the spotter says. Again the first guy fiddles with both adjustments, and shoots yet another single round. And his buddy says, “Ohmigosh! Now you’re two inches high, and way over on the right. Here, gimme that, I’ll do it!”

Those hunters are a little better off than the ones who “sight in” by leaning across the hood of the truck and shoot targets at unknown distances. But not by much. Maybe they’ve had a grand old time shooting away an afternoon. But they have not sighted-in their deer hunting rifles.

There are at least three major problems with the approach described above.

First: Nobody else can sight-in a rifle for you. Each of us holds a firearm differently. We mount it, and get down on the scope, in ways that are unique to us. These differences can have serious effects on how accurate deer hunting rifles shoot.

Second: One shot, no matter where it is placed on the target, tells us nothing. There is enough shot-to-shot variation, even with the best ammo, that only a group of several shots can really determine point of impact. Among serious target shooters, ten shots is the accepted number. Many hunters halve that. But even a three-shot group is acceptable.

Third: Sighting-in connotes determining what your deer hunting rifle is doing, absent any input from the shooter. In short, you want to remove the human influence as much as possible. And that means a solid, mechanical rest of some sort, which could range from a high-end, sighting-in rest to a home-made sandbag or three. Even a corrugated carton, with cut outs to support the fore- and butt stocks, is better than holding deer hunting rifles in your hands when sighting-in.

Understanding modern ballistics helps too. With almost all high-powered cartridges, if you sight in deer hunting rifles to hit the bullseye at 25 yards, your shooting will be approximately three inches high at 100 yards, then dead-on again at 200 yards, and within the ten-inch kill-zone of a whitetail out to, variously, 270-330 yards, depending on caliber and loading. So, if possible, start by firing at a 25-yard target. It will save you a lot of grief (and ammo costs).

Assuming the rifle has been bore-sighted, or previously sighted in, you initially should be within four inches of the center X. If not, be sure and have your target surrounded by enough blank paper so that you can see the impact, in case the scope is way off.

Seat the fore stock (not the barrel!) on your forward rest. If you have a rear rest, that’s better. If not, snuggle it tightly into your shoulder, supporting it firmly with your off hand and elbow. Sight on the bullseye, and squeeze off a shot.

Do not pay attention to where that round hits---and tell your buddy with the spotting scope to keep his mouth shut. Chamber a second round, sight on the precise same point, and fire again. Do that a third time.

Ideally, the three rounds will form a cloverleaf somewhere on the target. Chances are, though, they’ll be a little more open than that. Either way, figure the center point of the group. That’s you’re point of impact.

To figure the center, eyeball the group and choose the two rounds furthest apart. Then measure from the outside edge of one hole to the inside edge of the other. That’s the size of the group. Divide that number in half, and you have the center point.

Now, let’s assume the group, at 100 yards, is two inches to the left and an inch high. Each click of the scope adjustments will move the impact point a quarter inch at that distance.

Start by correcting one adjustment at a time. That is, adjust either the windage or elevation knob, but not both at once. Let’s say you choose elevation. Turn the elevation knob (the one on the right side, usually) four clicks in the right direction. Mount the gun in your rest. Ignore the first group entirely. Instead, sight at the same point you did originally, and fire another three-round group. That should form a pattern in, or evenly surrounding the bullseye. If not, make the necessary adjustment, and fire another group.

Once the elevation is dead on, repeat the procedure with the windage adjustment.

At this point, your deer hunting rifle is sighted in. But you’re not finished. You may not shoot the way the gun does. So, for your final groups, fire offhand. If the group is significantly off the bullseye, go through the adjustment routine again, to fine tune the rifle so that it shoots to center the way you hold it.

You’re now ready to hunt with a rifle that will do its job.