Your scope’s set up, but how do you properly zero it? (If you’re still working on the setup, check out my previous article, How to Zero Your Scope, before diving into the next step). Let’s get going!
Getting Into Position
An important thing to consider when zeroing the scope is that shooting position often affects point of impact. This is probably due, at least in part, to the different ways shooters aim in different positions, but it’s also likely a result of a different vibrations of the barrel. There are supporters of both these theories. I’ll let you decide to which you want to subscribe. Regardless, the problem is a real issue for zeroing, so the best way to combat it is to always zero the scope from the position you are most likely to shoot from on the field or at the range. If you are planning to go shooting long range on the field, shooting from a prone position, you should not zero from a bench, and vice versa. The difference may be subtle, but it amplifies with distance.
Once you are in position, the first step is to make a first rough sight in, so that are able to hit the zeroing target at 100yds. If you have a bolt action rifle, this step is very simple. You just need to remove the bolt from the action and aim your target looking through the barrel. When the breach circle is concentric with the muzzle circle, and you can see the target centered in the muzzle hole, you have a good sight picture. At this point, keeping the rifle steady, adjust the scope turret until the crosshair is in the middle of the target.
For this process, I recommend the use of a paper target of at least 20” X 20”, since with a smaller target it would be difficult to hit with the first shot after a bore sighting. The standard NRA High Power Rifle SR-1 targets are perfect for this purpose.
If you can’t remove the bolt, or if you are zeroing a semiauto rifle, you can use a laser boresighter, or make your first rough sight in at a shorter range, let’s say 25yds.
This first step is necessary only when you mount a new scope. If your scope has just been zeroed before, on a different ammunition or on a different rifle setup, you can jump directly to the next step.
Once you are sure to be on target at 100yds, you can establish your zero following this simple method:
Aiming the centre of the target, fire your first shot, which should hit somewhere in the target area. Keeping the rifle steady, pointed in the same position, adjust the scope’s turrets until the centre of the reticle covers the hole of your first shot. It is paramount that you keep the rifle steady during this process. To facilitate this process, you may want to have a friend help you by rotating the turrets while you keep the rifle steady.
At this point, shoot your first group of 3 shots, aiming always at the centre of the target. Your shots will now form a group very close to the aimed point. All you have to do now is repeat the previous process, adjusting the scope’s turret to move the crosshair on the center of the group, and your scope will be zeroed. You can confirm your zero firing another three to five shot string. If necessary, you can fine tune further from there.
For the fine tuning, I suggest using a target other than the SR-1. Personally, I prefer to fine tune aim at one corner of a small (1in) black square, making the horizontal and vertical axis of the reticle sit on the horizontal and vertical sides of the square. Many shooter uses a rhombus, or a small dot. I suggest trying a variety of solutions to see what works better for you.
During the zeroing process, it is very important to fire each shot with maximum accuracy, always applying all the fundamentals of marksmanship. Think of firing each round as making the most important shot of your life. It is also important to maintain the same conditions between each shot, avoiding position changes, holding fire if big variations in light (cloudy/sunny) occur, and avoiding heating up the barrel with sustained shooting. Remember that the accuracy of your zero will directly effect your ability to land your first shot accurately when you’re on the field.
Once you are done with your zeroing, if possible, “reset” your scope’s turret. Resetting the turrets means that you loosen each turret’s screws (or the relative lock) to allow the turret’s cap to rotate. Then position the turrets’ zero mark (or the 100 mark on a BDC—bullet drop compensation—turret) on the indicator on the scope’s tube.
In the next article, I’ll talk about an important test that you should make after you have zeroed the rifle: verifying the vertical symmetry of the scope, and verifying if the drop values of the scopes adjustments are true. See you then.