Boresight (firearm)

Boresighting is a method of visually pre-aligning a firearm barrel's bore axis with the target, in order to more easily zero the gunsight (optical or iron sights).

A drawback of using the naked eye to boresight is that it can be difficult due to the tunnel vision and lack of brightness, especially with longer-barreled guns.

A more modern method of boresighting is to use a laser pointer to illuminate the distant point of aim, rather than using visual inspection.

This method is preferable because it has less parallax, allows more movement in the gun as the projected laser beam will stay true to the bore axis, and does not require removing the bolt.

The user then adjusts the iron sights or scope reticle to align the point of aim with the projected laser dot.