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Boresighting without a collimator

Center a target in the middle of the bore.

Bore Sighting a Rifle

So you just bought a new scope, mounted it on your rifle and are ready for the range, right?  Not quite.  You need to bore sight first, or plan to shoot lots of ammo trying to get your shots on the target. And with the cost of ammo being what it is (if you can find it), it’s just plain stupid to not bore sight first.

Bore sighting is a rough alignment of the sights with the line of the bore.  It is not “sighting in” at all, but should result in your first shots landing somewhere on your target instead of down the berm so you can fine-tune your zero.

There are some excellent bore sighting tools available, and while many are inexpensive, it doesn’t make much sense to me to buy one if you don’t mount scopes very often. Instead, there’s a simple way to bore sight without a tool. It works great with bolt-action rifles, many single shots, but not at all on most lever-action and many semi-auto rifles.

To bore sight without a tool, place a target downrange and rest your rifle solidly on your sandbag rests. Remove the bolt, and look through the bore at the target. Move the gun around until the target is perfectly centered in the bore, and then look up through the scope. If it’s not aligned on the target, adjust the scope until it is. The trick is to make sure you don’t move the gun any between looking through the bore and looking through the scope.

After bore sighting, I typically fire my first shots at a 25-yard target and zero things there before zeroing at farther distances. With many centerfire rifles, zeroing at 25 yards conveniently is almost the same as zeroing at 100, but that’s another blog.


Scott Mayer


“Shooting Guns & Having Fun”

Scott Mayer
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