What is Bore Sighting?
Bore sighting is the task of matching the center of your bore to the center of your reticle as close as possible on a target so that you will at least be on the target (paper) when you zero (sight-in) your rifle. If you do not bore sight your shots may be way off target making it impossible to sight in your rifle scope.
There are many kinds of rifles, ammunition, scopes, and different scope ring heights coupled with the scope's mounting position to your eye relief. There is no telling how far off your point of impact will be. By bore sighting, even though not precise, will get you close enough to fine-tune it.
When bore sighting or working on firearms first, ensure it is not loaded and always pointing in a safe direction.
There are many ways to do it, and everyone has their preference. Here are some of the most popular ways to bore sight.
How to Bore Sight Your Rifle Scope with no Tools.
If you can pull out your bolt and look down the bore, you can bore sight without any tools.
Pull out your bolt and set your rifle on a rifle rest like sandbags made for shooting where so that it is as secure as possible.
Set a target as close as 12 feet to as far as 50 yards as long as you can see and center the target in the center of the bore. The further you place the target, the less elevation you will have to adjust when you go to zero. If you do happen to bore sight at shorter range, use a target that you can center on. Even a matchbook cover cut in a circle and placed 12 feet away can work.
You will also need to visually check that you are looking down the center of the bore. What I mean by this is when you look down the bore, you need to position the rifle, so you are looking straight down the center of the bore as close as possible so that your bore forms a perfect circle with the target in the center.
Like this
Not Like this
Then, while being very careful not to move your rifle, turn the windage and elevation dials as needed to center the reticle on the center of your target.
Like this
The center of the target should be centered in the center of your reticle with your target centered in the center of your bore like this
If they match, you should be ready to fire a round and see where it hits. If you did it right, you are bore-sighted, and you should close enough to zero your scope.
Using a Laser Bore Sighting Tool
If you cannot remove your bolt, you will need a bore sighting tool. A laser bore sighting tool is easy to use. Some are shaped like a cartridge case and fit inside your rifle's chamber. Follow the manufacturer's instructions. These are used by carefully chambering the laser, and a laser is beamed through the bore onto a wall. Then align the center of the reticle to where the laser dot is, and you are ready to zero your rifle. These will require different slip-on chamber arbors to match chambers
The other kind of laser bore sight is the one that fits in the muzzle. These are probably the easiest to use, but you must follow the manufacturer's instructions to get an accurate reading. They also produce a laser dot on a wall to adjust the center of your reticle to where the laser hits to bore sight. You will not need arbors for this one. A plastic tip screws on one end for different calibers and centers it in the bore, while the front part self-centers in the muzzle.
Bore Sight Grid Tool
The professional Bore Sighter Tool is another bore-sighting tool that many gun stores and gunsmiths use. This one also uses arbors but does not transmit a laser. You attach the bore sighter and align it with your scope. You will see a grid inside the bore sighter, and align your reticle with the grid following the manufacturer's instructions.
At Warne Scope Mounts, we sell scope rings, bases, and rails so that once you are bore-sighted and zeroed, you can have confidence that the scope mount will do its part to keep you zeroed. Use our specs to check compatibility. For example, Warne Mountain Tech Picatinny rails are (NATO) STANAG-compatible. Because shooters design them for shooters, all our equipment and accessories are field-performance proven.
Now you are ready for the range to zero your rifle. See our article How to Zero Your Rifle Scope - Warne Scope Mounts.