Centerfire Boresight with Red Laser

I have four of the Sightmark laser boresights - the 12 gauge, 9mm, 7.62x39mm, and .223. I had used a Bushnell laser boresight before getting this set of chamber loaded laser boresights. The Bushnell is the kind that you stick into the muzzle end of the gun, fitted with an arbor matched to the barrel size. The problem with this device was that the arbors never fit quite right - they were always either too tight or too loose, plus you had to try to seat the body of the boresight in the center of the opening of the barrel (or muzzle brake) in order to properly align the center axis of the boresight with the center axis of the barrel. This rarely if ever happened just right as the slightest tilt in the seating of this boresight in the barrel would take it off the center axis so that rotating the laser would cause the laser light to mark out a small circle that was several MOA in diameter rather than being dead centered. Ugh. Of course with these chamber loaded laser boresights, there is also the potential for the lasers to be mis-aligned off the center axis. Plus there is the potential for the boresight to not fit the chamber properly. The key is to find a brand that has a measure of quality control so that you aren't stuck with these problems. I read through a lot of reviews before deciding on Sightmark. It is definitely not the cheapest out there. There are so many different brands and generic versions of these chamber loaded laser boresights now that almost look alike, with many much cheaper than the Sightmark. However, it was clear from reading the reviews that as the prices went down, so did the quality control. Several of these cheaper brands came with complaints that the lasers were not aligned to the center axis (resulting in the laser painting a circle as it rotates in the chamber) or that they did not fit properly in the chambers and so would either get stuck or wiggle. I have this theory that the really cheap laser boresights must be factory seconds or some such. I considered the Osprey line with the adjustable arbors, which saves money by allowing you to use one laser bore sight for different calibers. But, the reviews indicated that hassling with arbors would have an effect on accuracy and reliability. I almost got the Firefield, which seemed to have a similar number of decent reviews. Ultimately I decided against it because the entire line is made of an aluminum shell, and I think the brass shell of the Sightmark will hold up better. It should be noted, however, that the 12 gauge Sitemark is made out of aluminum, unlike the others, and is only painted a brass color. The biggest complaint against all of these laser boresighters are the frequent DOA batteries and poor battery life. The Sightmarks all come with alkaline button cell batteries. The small caliber ones (9mm, 7.62mm, .223) come with two AG5 batteries while the 12 gauge came with three AG13 (LR44) batteries. To get you all confused, the printed information on the back of the packaging for the 7.62mm and .223 says you can use 3 AG3 batteries in place of the 2 AG5 batteries (since the AG3 is a thinner battery with the same 7.9mm diameter), while the printed info for the 12 gauge says you can use 2 AG5 or 3 AG13 batteries. This is flat out incorrect since 2 AG5 batteries are too small to fit into the 12 gauge Sightmark battery chamber. Confused? Go to wikipedia and look up the article "List of battery sizes". Scroll down to the section titled "Silver oxide and alkaline cells". The table lists all the different names for each battery, their dimensions, and their mAh power rating. Note how the silver oxide batteries contain 1-1/2 to two times as much energy as the alkaline batteries. So the key is to go out and get some silver oxide button batteries, size SG5 for the AG5 powered Sightmarks and SG13 for the AG13 powered lasers. And don't go to your nearest retail store, since that will cost you an arm and a leg. Google shop for these batteries online. I found two Made in China "brands" one called Vinnic and another by Chung Pak Battery Works which were pretty cheap. The names aren't important, since I'm sure they will change rapidly. Just remember to get some silver oxide batteries online at the same time you are getting these Sightmark bore sights. How well did these Sightmarks work? The very first time I used one (the 7.62x39mm), I plugged in the included AG5 alkaline batteries and the resulting laser light was exceedingly weak. My initial reaction was that this was a bad laser. Then I remembered the silver oxide batteries I had gotten. When I switched out the batteries, the laser suddenly glowed brightly. Later, when this set of silver batteries finally wore down, the laser light faded again. That's a sign to change batteries. The larger AG13 alkaline batteries for the 12gauge shotgun boresight worked reasonably well and are still working as of this writing. Not surprising, since these batteries pack a lot more energy than the small AG5 batteries. As many have noted, the Sightmarks do not have an on-off switch. Once the batteries are screwed in the laser light is on! This is just as well, since the bore sights have to flush fit inside the chamber of the barrel and endure having the bolt and firing pin slammed into them. But you do have to have a plan of action ready so as to not run down your batteries. With one pair of SG5 silver oxide batteries, I was able to adjust the sights for about four guns, each taking about 5-10 minutes. So I am guesstimating a battery life of about 30 minutes with a fresh pair of SG5 silver batteries (the Sightmark packaging claims up to an hour of battery life - hah!). All of the Sightmarks have fit in well, none have gotten stuck (so far), and none have had off-center lasers. These chamber loaded Sightmark boresighters make it easy to dial in a scope, and for fixed sights, they help confirm the aim points. They are much better than the muzzle loaded bore sights, although the total cost is a lot more since they are ammo caliber specific.

CONSTRUCTION: The laser body is made of sturdy brass, nicely finished, and with an excellent fit for the firearm caliber. The version I purchased is for a .308 Win caliber rifle. The laser is perfectly aligned with the barrel axis, so it won't make fringes once it's manually placed in the chamber. If you follow the instructions that came with the laser you'll zero in your rifle in no time...and without spending a lot of rounds in the process. (A note to semi-auto firearm users, such as M1As: after manually inserting the sight laser into the chamber, do NOT slam the action as you would with a normal round - this will damage the laser. Instead, SLOWLY advance the action until it closes the breech. This note is in the user's manual, too, but it won't hurt to note it twice.) ACCESSORIES: The laser comes with a small holster for storage, made of ballistic nylon. The holster is large enough to store the laser, its batteries and the user's manual. {However, it is small enough to lose it, too. ;-) }. It comes with a set of two button-size batteries (LR 754). Some things to note: - it's not a high-intensity laser. Therefore, you may have difficulty seeing the laser beam at 25 yards in the open on a very sunny day. - due to its size, the laser uses two button batteries (LR 754), and those don't last a long time. My recommendation is to keep the batteries in the provided pouch until ready to use, and to carry a spare set just in case. CONCLUSION: For what it was designed, it does an excellent job. I wish the laser intensity would be higher, or be of a different wavelength (color; e.g. green) for better visibility in bright, sunny light. I will definitely buy it again if I lose or damage it (I hope I won't), provided the company is still there if that happens.

I used this to sight in my .308 M1A rifle. I got a new Vortex scope and a Basset Machine mount for the holidays and took it out to the desert to get it sighted in. I couldn't even get it on paper, so I decided to quit wasting ammo and get a boresight. The Sightmark boresight came with batteries and simple instructions. I put the batteries in and the laser lit up. Once I got it chambered I matched up the laser dot with the reticle and that was it. I did it in the late afternoon so the laser dot would be bright. My aim point was about 20 yards. Of course, at the range I would have to adjust the elevation for shooting at 25 or 50 yards, but windage should be the same. Sure enough, I was on paper and had to adjust the elevation while the windage adjustment was minimal. In sum, this product worked perfectly to get my scope on paper. Some notes: 1) There is no on\off switch; once you put the batteries in and screw on the cap the laser is on. You have to take the batteries out when you're done. They are tiny little things. I used the corner of a plastic sandwich bag and rolled them up in it, and it fit in one of the little pockets in the fabric case. 2) Open the bolt and seat the boresight in the chamber as you would load a single bullet and don't let the bolt slam close as this would probably damage the boresight. 3) This is a low power laser, so you're not going to be able to see it on a bright day at 50 yards. Probably not even at 25 yards. That means you need to use it indoors or at around dusk if you use it outside. Using it indoors will limit the distance you can set your elevation at, but the windage will not be affected. 4) Boresights are not designed to set your scope for the bulls-eye. They help you get close enough that you're hitting your target, and you can go from there to get an exact adjustment.

I purchased this boresighter to sight in my AR and any other rifles this will fit in! The only issues I've come across with is that the battery drains fast like within an hour of use and it'll start to dim after that which makes it not visible even at night at 100 yards! Quick fix for that is purchase a 20 pack of the batteries on here for $6 shipped and you're all set! **Update** 12/4/2013 I've been using this SightMark for over a year now and have to say it holds up very well! The brass casing, much like ammo casings, fades to a darker color due to the oils on hands when handling over time, but the laser still works great! I've actually used this as my main bore sight over the last year to sight in a 30-30, 5.56 (.223), and even a 10/22!! Works great every time, but as I've previously mentioned, it only runs about an hour so pick-up a bulk pack of batteries and you'll be set! Sighting a red dot sight can be tricky as this laser doesn't show through the lens of some of them, but I've managed to see it most of the time it's just really small and dim through the lens. Of course you can always sight in an AR by just looking down the barrel and lining up a red dot sight for the distance you want, but this isn't as easily done on other types of rifles like the 10/22. For sighting in a 10/22 I had to take the bolt carrier out and just hold the laser to the barrel and line it up straight, kinda works and you can make fine tune adjustments at the range. Still a great product!

Before I start I want to state that it looks like Amazon has the reviews for all the versions in one area. I'm writing a review for the .308 version, and used this on my Remington 700. I recently purchased a Rem 700 and Vortex optic for it. I got everything mounted on the gun and ordered the this boresight via Prime and it arrived on time without issue. I tested it in my house and saw the laser lit up fine and headed out the range this past weekend. Ideally I wanted to sight in my rifle at 100 years but after reading the direction it said to do it at 25. So I set up the target at the 25 yard line. Put the batteries in and saw the laser light up, then put boresight in the chamber and closed the bolt (the .308 version I got does not have the external battery pack and wire coming out, instead it uses hearing aid size batteries x2). After looking in the optic I could not find the laser dot anywhere on the target, my friend and I held a piece of white paper in front of it and walked out towards the target to see how far we could see it. At about the 10 yard mark it was barely visible and not visible at all at 25 yards. We pulled it back out and it looked as if the batteries where already dying off. At this point I was annoyed and assumed that the batteries where old as maybe it was sitting around Amazon's warehouse for too long. Headed home and figured I would get new batteries and try again in my house to at least get it so I can be on paper with the optic. On the way home a ran by wallgreens anre grabbed some brand new Duracells and once home put them in the boresight, to my amazement even with the new batteries I could not see the laser across my dark garage. It was just as bad as at the range if not worst. At this point I plan to do an exchange to see if maybe I just got a faulty one. If thats the case I will update this review.

I own several different laser bore sights by Sightmark, in a number of different calibers. I also have one of their universal laser bore sights. I've found all of their products to work quite well so far. I've found these in the chamber type of laser bore sights to work much better than the universal types which hang out from the muzzle. The machining on these in the chamber types by Sightmark is quite good. With the firearm firmly mounted in a heavy bench rest, I've rotated the sight to several positions in the chamber and seen very little change in the point of the dot even at 100 yards, which indcated to me not only a very good machining but also a very good adjustment of the laser within the brass body. One thing to bear in mind with these sights are that while they do feature a rim like a standard cartridge, the sight is not meant to be removed from the chamber by means of the extractor and bolt. While you will get best results by gently letting the bolt close and push the sight snugly into the chamber, the sight will not simply fall out upon opening the bolt and again, it is not meant to be extracted like a standard cartridge. to remove it is best to open the bolt and keep it open while using a cleaning rod from the muzzle end to gently push the sight out from the chamber. Another thing to bear in mind is that none of these types of sights are perfect. They will do a little better than just getting you on paper, but you will still have to go through the usual steps of zeroing your sights or scope. Consider the distance that you are looking to have as the zero. Even though it is a laser, the diameter of the dot will increase over distance as will any very slight variation from true bore line center. Getting on paper and close to target center at 100 yards with such a device is still doing quite well. At 25 to 50 yards though these devices are outstanding. Be aware too though that even with a powerful spotting scope, it will not be easy to see the red laser dot in full daylight at distances beyond 25 yards. It's best to use the sight in lower light conditions.Factory ammo will also give considerable variation in points of impact. The amount of time and ammunition saved by using one of these sights makes them well worth using. The only two things about these sights that I could see as an improvement, would be some sort of switch rather than having to remove the batteries, and having a green laser instead of red. Given the infrequent need to use the sight however, makes the lack of switch and the need to remove the batteries an extremely small complaint. With current technologies in batteries and lasers having a green laser in such a small package is very unlikely and the cost would be considerably higher.

I picked one up for my AK-47 and it worked flawlessly. I inserted the batteries, slid it into the chamber and was presented with a nice red laser dot. It certainly did make it easier to zero the weapon. Very cost effective as I can use it again should I change my red dot or decide to use a scope instead. Of course, you can loan it to your less intelligent buddy who didn't think to get one and it obviously can be used on any 7.62 gun. Sure, 7.62 rounds are currently going for around 20 cents a round, but that adds up if you have trouble zeroing in. (I watched my son fire off 50 rounds with his AR-15 without using a bore sight and he wasn't even close to getting zeroed. It turned out to be an issue with his scope, but with a bore sight he would have figured that out a lot sooner. I had no issues with my bore sight. It aligned perfectly. Apparently, some people get lemons that weren't properly calibrated at the factory. I strongly suggest returning it for a replacement. It's not going to cost you anything since you bought it on Amazon. Odds are that you're replacement bore sight will work perfectly. I don't care for the fact that in order to turn the laser on you must open the bore sight, insert the batteries then tighten the cap. To turn it off you must remove the batteries. No on/off switch. For the money I guess that's expected, but wouldn't it be nice to slip the bore sight into your chamber and have it come on automatically when you close your bolt? This is just a minor irritant as I don't have to use the bore sight every time I go to the range. Other than no on/off switch I'm perfectly happy with this purchase which is why I got one for my AR-15 too.

This is the fourth caliber I have purchased, although I have not actually tested this exact one yet. The concept is very good, the manufacturing tolerances leave a lot to be desired. For the price, they should work better, but I keep buying them (grudgingly) because I finally figured out how to make them SORT of work for me, at least better than other products that I have tried. I originally bought this product for three reasons: 1) To help me bore sight some scopes that I was installing. 2) To use to check the accuracy of some QD mounts when I re-installed some optics that had been previously sighted in. 3) To check my scopes after traveling or having them bumped. Within reason, and with some practice, they work well enough for the first reason, but not well enough for the second two. They are somewhat better than the muzzle mounted lasers, but they are not as good as they could be. I gave up on using them to check the accuracy of a QD mount re-install in the field as they are not consistent enough, even with the trick below. After flying I would for sure take a practice shot to check my scope rather than rely on these things. The problem is they are not centered well. Not one of three calibers I have tried so far has been dead on. If you insert them 3 times in the same gun, they will point to three different spots. The difference is noticeable even as close as 15-20 feet away. If you can manage to spin them while they are inserted in the chamber, you will note that the projected dot makes a circle several inches in diameter on a surface 15-20 feet away. If I was mounting a scope one time on a bolt gun, I'd save my money and just put the gun in a solid mount, remove the bolt, and look down the barrel to get it on paper. The few extra rounds you burn will probably cost a lot less than this gizmo. However, if you have to install several scopes, or like to swap optics out pretty often, you can make them work pretty well by doing the following. Insert the laser into the chamber and attempt to spin it. While looking through your scope, watch the projected red dot move in a circle on a surface 20-30 feet away. It helps if you look through the scope and someone else spins the laser cartridge, because it's not easy to do. Try to get the laser cartridge positioned so that the dot is at the highest point on the circle. If you can't spin it while it's in the chamber, note where it points in relation to your cross hairs, and eject and re-install it several times to find the highest spot in relation to your cross hairs that the red dot ever points to. While it's still inserted, lightly mark the upper edge of the back of the laser cartridge with a fine point marker so that you can repeat the installation the same way each time in the future. (You will never get it inserted exactly the same as you initially had it, but if you get your mark as close to straight up as possible each time, you'll be within a few MOA.) Now make your scope adjustment in relation to the red dot and you should be almost perfect on wind-age when you go to the range. Hopefully, you should only have to adjust your scope cross hairs up or down a bit, but not left or right very much. You have to remove the batteries to turn these things off. The case does not hold the batteries well, something that really irritates me when that would of been such an easy fix. Keep the entire case in a zip lock bag or you will lose a battery. Also, these things eat batteries are a very fast rate. Buy some extra ones when you order the product. The markings on the actual batteries do not correspond to any that I could find locally. It turns out that everyone else calls them something else, so if you have to buy extras at the store, take a dead battery and not just the package the factory ones came in. Note: if you don't think you will need to use these very often, and when you do, you think that you'll need several calibers, then the muzzle mounted laser might be better deal as you only have to buy one item for multiple calibers. Just get the arbor as tight as you can in the muzzle, and then spin the laser to find the top of that circle. Working off the top of the circle or arc, you should be pretty close on wind-age. I have not found a device that I would trust to check a QD optic remount, or the zero on a scope after air travel.