This is from the Q&A on our Amazon ad HERE. Q: Can I use the Taryag Laser Cartridge to adjust my crimson trace sight? in addition to dry firing? A: SELLER’S ANSWER: I am an NRA Pistol Instructor and FFL, and I build 1911s. After using this laser cartridge to adjust hundreds of sites, I can report from experience that adjusting sites with the laser cartridge is nearly the same as doing it with live ammo – which is how it was always done in the past. Here’s a YouTube clip showing how to do it with live ammo: Sighting-In Handguns With Adjustable Sights But, with the Taryag Laser Cartridge, you can do it just as well at home. Most people adjust their sites at about 25 ft. or 10 yards. First, set up a target or pick out a spot on the wall. Then, simply take aim with your existing sites and fire a shot from the laser cartridge. You don’t even need to mark the hit on the target; simply adjust your sites or OEM laser in the necessary direction to match the laser cartridge. Repeat the process a few times as needed and, when the OEM laser or iron sights point exactly where the laser cartridge is hitting, they’re properly adjusted. The laser only flashes for about 10 milliseconds, but you’ll have no problem remembering the hit location – it imprints on your retina for several seconds. If the laser stayed on any longer, the dot would appear as a streak, so it would be impossible to identify the hit location. Incidentally, laser cartridges are sometimes called “training cartridges” and sometime “bore sighters”. But, “bore sighters” can also refer to the laser devices that are inserted into the muzzle of a rifle. You have to read the description to know which is being referenced. Muzzle bore sighters are typically too long to fit a short barreled revolver or semi-auto. Also, the rifling at the muzzle crown can sometimes interfere with the proper seating of the device. Revolvers present an additional problem – please read my .38 Special Note on the TARYAG Laser Training Cartridge and other ads. Hope this helps!