Pistol Boresights

I bought the 9mm version. I used it to adjust the iron and red dot sights on a 9mm carbine at 25 yards. The laser is only so bright, so you're either going to have to do this indoors, or outdoors on a less then bright sunny day. My unit came with 2 AG5 batteries. It will also accept 3 AG3 batteries. There is no on/off switch, when the batteries are in, the unit is on. I suggest you take them out when you're done. I had mine running for about 45 minutes on the batteries that it came with without noticing any change in the lasers brightness. After sighting in the iron sights at 25 yards, I experimented by rotating the boresight in the bore 90 degrees at a time to see if the laser was still aligned with my sights. I noticed no difference at that distance. My red dot is mounted on an American Defense quick detach mount. It was interesting and educational to use the laser to sight in the red dot. After my initial sighting in, I used my hand to flex and twist the sight on it's mount while it was attached to the rail of my gun. Guess what? It was clear I needed to tighten my mount! Then I used the laser to see just how well the red dot would hold zero when repeatedly removed and replaced on the weapon. Again, at 25 yards, I couldn't tell a difference. Finally, as I had done with the iron sights, I rotated the boresight 90 degrees in the bore, rechecking it each time against the red dot sight. Everything looked good! After all that, I switched to live ammo to check my efforts. I was off about half an inch high to the right. Fantastic results as far as I'm concerned! I'll sort out the rest at the range. I consider what I paid for this device money well spent for what I've used it for so far. Mine was a tad tight in the bore, even after cleaning the bore carefully and applying a VERY light coat of oil, I still had to use a pair of needle nose pliers to carefully extract it each time I removed it. I don't consider this an issue, just passing along my experience.EDIT: April 10, 2016 - Just a quick note on batteries, The second time I took this thing out to use it, the original AG5 batteries it came with were dead. The laser came on when I put them in but before I could use it, it sputtered out. I had bought a package of 10 Maxell AG3 batteries at the same time I ordered this boresight so I put in 3 of them. They lasted 10 minutes at best! I don't know exactly what to make of this information. Are two AG5s inherently better then three AG3s? Are the Maxells I bought just old or crappy? This much I can tell you, you gotta work quick to get anything done in 10 minutes...

I recommend using a vise to hold the gun firmly in place for the entire zeroing, so that the "point of impact" revealed by the boresight - marked on a target paper in ink - can remain fixed, the battery can be removed, and the point of the adjustable gunsight can be adjusted (whether red dot or laser sight or barrel gunsight) to coincide with where the boresight was set.It fit perfectly the 38 special it was bought for. I thought it might also fit 9 mm, and even 380 cal - it does not. Strangely, the rim is undersized - the ejector of the revolver cylinder does not catch it to eject it - but I don't hold that against the company; the item works as advertised on what it was designed for.The laser was centered perfectly - straight down the center of the bore - for the 50' distance to the target I wanted: rotations of the boresight within the revolver cylinder produced no visible "circling" on the target.Battery life is not advertised to be long - I think it was to be <1hr of actual "laser on" time - so don't waste time. Take out the batteries when you've learned what adjustments need to be made, replace them only when you are ready to actually verify, then remove them again. It's all easy enough.

Bought the laser bore sighter for 9mm. Pass this one up. Typical Sightmark QA. Build quality is shoddy, sighter gets jammed in the chamber, requiring a non-marring rod to pop it out. Tried using it, adjusted my red dot, popped it out. For fun, I reinserted the sighter. Off again. Readjusted my red dot. Removed and reinserted again. Off again. Obviously, the laser is off-center out of the box. Returned.Don’t waste your money, just buy a Site-Lite and call it a day. Yes, it’s more expensive. It is also much more reliable, better built, and yields more accurate results.

I purchased this item for my Hi-Point C9 to help me better sight it in at longer ranges. The item worked great as far as the laser working, batteries and fitting well in my pistol. It also is good to get the general idea of where the POI will be at the distance you wish to set your gun up for with your particular site picture.The only thing is that this boresight is not useful at all if you are outside in the sun. There is no way on earth to see the dot in daytime conditions at 15 yards which is where I was trying to sight in my gun. This may be the case with all boresights and not something that is a major issue with this specific one. Pardon me if I am a newbie to them but the best way to learn sometimes is by trying different things. I would suggest that this boresight be used inside at a range or in your house if you have the distance needed. Or you could wait until dusk if you definitely need to sight in your gun outside.The last thing is that the boresight will not self extract from the chamber like a normal shell would. Of course this is probably by design so to insure a snug fit in the chamber to make sure it is centered properly. Not an issue but can scare the crap out of you when you first go to use it (especially if you don't read the operating instructions like me to know to use the end of an eraser on a pencil to dislodge it).I am very happy with my purchase of this item but I thought it may help others make a decision from my observation and mistakes.