Since most hunters use telescopic sights on their rifles, this article describes how to sight in a rifle with a scope. After mounting a new scope on a rifle, it is important to ensure that the reticle is completely level. Even a slight cant to the reticle can throw off the impact of the bullet and make the scope much more difficult to sight in. Also, ensure that the scope is secure in the rings and that the rings are tightly mounted to the base. There should be no wiggle whatsoever to the scope.
Before actually shooting the rifle, it is best to bore sight it. First, ensure that the rifle is unloaded and that the barrel is unobstructed. Then, remove the bolt of the rifle and mount the rifle in a secure rest pointing downrange.
Standing behind the rifle, look through the bore and carefully move the rifle until your target is centered in the bore. Then, without moving the rifle, adjust the scope so that the reticle is centered on the same target.
The turret on the top of the scope adjusts the elevation of the reticle, while the turret on the side adjusts the windage. It is not vitally important for the bore sight to be extremely precise. It just needs to be close enough so that the rifle will be on paper at 25 yards in the next step.
Your view when looking down the bore of the rifle should look something like this.
After bore sighting the rifle, you’re ready to start shooting. I like to shoot at 25 yards first, then fine-tune my zero at longer ranges. I’ve learned that this saves time, ammunition and frustration in the long run by avoiding taking shots at 50 or 100 yards and not hitting the paper.
The exact target doesn’t really matter at 25 yards as long as it has a distinct aiming point. Some people use bull’s-eye targets with lots of success. I prefer to use a dedicated zero target that Lucky Gunner provides for free because it has an easy-to-use grid format that helps me determine my adjustments.
When sighting in your rifle, it is extremely important to shoot from a stable position with lots of support. Use sandbags or a specially built rifle rest to do this. Whenever possible, avoid supporting the rifle with your muscles, as this is less precise than using a stable object like a sandbag.
Finally, focus your scope on the target at which you are shooting. This will give you a crystal-clear view of the target and make the shooting easier. Most scopes have a dial to focus the lens, which is normally located at the end closest to the shooter. You can see it on my rifle in the first photo. It’s the dial located on the end of the scope, just to the left of the word “Conquest.”
Once you’re set in a steady position, fire at least three shots at the center of your target at 25 yards. If you’re using a high-magnification scope, you may be able to see the holes your bullets make in the target.
No matter where you see the bullet holes in the paper, do not change your point of aim. Keep aiming at the bull’s-eye, or you’ll end up chasing your shots all over the target. It’s OK if you don’t hit the bull’s-eye at first. In fact, it’s almost guaranteed that you won’t.
After you fire your first group, check the target to see where you’re hitting. Measure from the center of your group to the bull’s-eye and adjust your scope accordingly. Most rifle scopes have 1/4 MOA adjustments. This means that one click will move the bullet impact a quarter of an inch at 100 yards.
However, this means that you need to make four times the number of clicks (16 clicks = 1 inch) to move the bullet impact the same distance at 25 yards. For example, the point of impact on the target below needs to be moved 1/2″ left and 1/2″ up. At 25 yards, that would be eight clicks each way.
At 25 yards, adjust the scope eight clicks left and eight clicks up.
As stated above, the turret on top moves the bullet impact up and down, while the turret on the side moves it left and right. As you can see in the photo below, most scopes have the measurement increments annotated on the turret, along with the proper direction to turn it. In the case of the scope on my rifle, turning the turret clockwise will move the impact of the bullet up or right, depending on which turret you are adjusting.
For example, assume that I shot a group at 25 yards that hit 1″ low and 4″ to the right with my rifle in the photo above. Since I need to move the bullet impact up and to the left, I’d turn the top turret 16 clicks clockwise and turn the side turret 64 clicks counterclockwise. A trick I learned in the Army is to go several clicks past the required number, then go back.
For instance, I’d go 21 clicks clockwise, then 5 clicks counterclockwise on the top turret. After that, gently tap the turret several times to ensure the adjustments are locked in. This is even more important when making large adjustments or when using low-quality scopes.
After making the required number of adjustments, shoot another group at the bull’s-eye. If that group hits where you’re aiming, you’re ready to move the target out to 100 yards. If not, make the necessary adjustments to the scope and shoot until the rifle is dialed in at 25 yards.
Using the same techniques described earlier, shoot a group at 100 yards. Since you zeroed the rifle at 25 yards, it should be at least hitting the paper at 100 yards. Measure the distance from the center of your group to the bull’s-eye and adjust the scope as necessary. Remember: four clicks equals 1″ at 100 yards, not 16 like at 25 yards.
When zeroing at 100 yards, your windage should be dead on. However, there is some debate as to where your shots should be hitting elevation-wise. If you’ll be hunting at a relatively short range, then it might make sense to adjust your scope so that the bullets are hitting the bull’s-eye at 100 yards.
However, sighting in your rifle so it hits slightly high has advantages as well. Each rifle is different, and an ideal 100-yard zero varies. Using my rifle in the photos (a Ruger M77 in 9.3x62mm Mauser) as an example, I sight it in so my shots hit about 2″ high at 100 yards.
With this setup, the bullet will hit about 1″ high at 50 yards, about 1″ high at 150 yards, dead on at 165 yards, and about 3″ low at 200 yards. This means that without having to adjust my scope or my point of aim, I can take a shot on a deer out to 200 yards and still hit the vitals.
After you’ve made your final adjustment, fire one last group to confirm it. If the group hits where you want it to, you’re done. A good scope will hold your adjustments for a long time, certainly through hunting season, as long as you don’t drop the rifle or otherwise damage your scope.