The 10 Best Boresighters
This wiki has been updated 26 times since it was first published in September of 2015. Competitive sporting shooters will appreciate the accuracy delivered by these laser boresighters, which will have you hitting the target the first time more often. They make it easy to align your firearm barrel and sights, which makes zeroing so fast you'll be able to spend more time honing your sharpshooting skills. Firearms are extremely dangerous - always practice good muzzle discipline. When users buy our independently chosen editorial recommendations, we may earn commissions to help fund the Wiki.
February 13, 2020:
The SiteLite Ultra Mag SL-500 is a truly universal boresighter that produces excellent results whether you're using it on a handgun or a hunting rifle. It even includes a scope leveler so that you can be certain that you're working off of a good platform. As far as optical vs laser boresighters, many laser sighters can be quite limited during the day, which is why some prefer the optical models like the Bushnell 743333 - they are perfect for day use but they do sacrifice some of the accuracy that you get from laser models.
The next thing to consider is that most boresighters will mount either at the muzzle (the end of the barrel) or the chamber (the start of the barrel). I tend to prefer chamber-loaded sighters because it completely eliminates any chance that you'll damage the crown when zeroing in. When you do damage to the crown, even small imperfections can be wildly detrimental to your gun's accuracy. You should also keep in mind that even after zeroing in your sights with a laser or optical sighter, you'll still have to tweak your sights or scope to account for bullet drop and other conditions. This is merely the nature of zeroing in - it is not your boresighter's fault.
Firearms are extremely dangerous and users should always practice good muzzle and trigger finger discipline to minimize the risk of personal injury or death.
Choosing The Best Boresighter
Consider an option that adheres to a barrel magnetically, as it can be rapidly installed and removed, allowing for fast and accurate sighting in multiple weapons.
Using a boresighter is a great way to ensure that your rifle or pistol's sight or scope is as perfectly aligned as possible. Boresighters allow for accurate zeroing in without the need for lots of shots fired, which means less wasted ammunition and which allows for the proper sight alignment of a firearm even when you're not at a shooting range or out in the field.
In fact, the investment you make in a laser boresighter will almost always pay for itself in terms of all those rounds you don't have to fire; this savings may take a while to accrue if you are shooting a .22 caliber rifle, but it is especially true with something like a .50 caliber BMG rifle, a weapon for which each round can cost more than five dollars.
And in fact, not all boresighters are even that much of an investment. You can get a decent laser boresighter for less than fifty dollars and acquire a tool that is suitable for most uses, such as sighting in a hunting rifle or making sure a pistol that will be used for home defense purposes is accurate enough to prevent errant shots at close range. If you are going to get a lower cost boresighter, make sure it offers at least a few features such as adaptability with various types of sights, such as an optical scope, a laser dot, or the iron sights that likely come as the stock option of your firearm.
Keep in mind that while many lower cost boresighters are perfectly suited for most shooters, they may not produce a laser that is readily visible in bright sunlight (at least not at far ranges) and they might not work well enough for competitive sport shooting or for tactical purposes.
For the shooter who demands the best possible accuracy from his or her weapons, a high end boresighter is a must. You will spend well over one hundred dollars for a great sighting tool, but top-of-the-line laser boresighters can be used in broad daylight with a green laser or in lower light with a red laser, and they can be used in all sorts of different weapons.
Consider an option that adheres to a barrel magnetically, as it can be rapidly installed and removed, allowing for fast and accurate sighting in multiple weapons. It also eliminates the potential for scratched rifling that can affect the ballistics of bullet's flight.
However, it must be noted that magnetic boresighters can only be used on firearms with muzzles that are perfectly flat (indeed most are). A boresighter that is inserted into a weapon's barrel is a must for any gun with an irregularly shaped flash suppressor, for example.
Using Your New Boresighter
Most boresighters can have a competent shooter hitting the bullseye within three shots. Before worrying about your boresighter, however, you have to establish a proper shooting platform -- if your weapon is not stable, you can never hope to sight it in properly. (With pistols, more often than not you are your own shooting platform; more than three shots will likely be required, as will plenty of patience.)
And of course do not forget to remove the boresighter from a firearm before you begin shooting the weapon.
Use a dedicated rifle mount perched on a shooting table or rifle bipod to get your long gun set up and aimed as accurately as possible at your target. Make sure you have properly measured the distance from your weapon to the target if you are not shooting at a professional range -- even a few feet of improper measurement can render your efforts ineffective.
Be sure to select the right adapter (or make adjustments to an affixed adapter) for your weapon's barrel caliber before inserting the boresighter. Using an adapter that's too small will reduce the efficacy of the sighting process and trying to insert one that is too large can damage the firearm.
The point of a boresighter is to minimize the number of shots you take when zeroing in your sights. Take the time to adjust your sights to align with the laser's dot before your first pull of the trigger. Chances are that your first shot will be near the bullseye, and with slight adjustments, your second will hit dead center.
And of course do not forget to remove the boresighter from a firearm before you begin shooting the weapon. While this step might be hard to overlook with a handgun, a shooter with a rifle mounted on platform just might forget that his or her barrel is obstructed. The result will be a ruined boresighter in the best case scenario, and a badly injured shooter in a more serious situation.
A Brief History Of Boresighting
Use of a boresighter is hardly limited to the shooter hoping to get his or her rifle zeroed in before the hunting season or before a shooting competition, and it is hardly a recently developed technique, either.
This includes everything from a fighter aircraft to an attack helicopter to the main gun of a battle tank.
In fact, rudimentary bore sighting was first practiced centuries ago by musketeers and cannon crews attempting to get the best aim out of inherently inaccurate weapons. In the early years of the firearm, the issue was less often if a weapon's sights were accurate, but rather whether or not its barrel was anywhere near to being straight.
Bore sighting is also a necessity for proper accuracy with the large weaponry built into military vehicles. This includes everything from a fighter aircraft to an attack helicopter to the main gun of a battle tank. Bore sighting was as necessary a step for the planes flying the skies over war torn World War II as it is for the advanced vehicles prowling the air and the ground in today's battlefield. And even today, most bore sighting is conducted by a person physically inserting a boresighting device into the barrel (also known as the bore, of course) of a gun or cannon.