Home Forums Hunting & Shooting Backpack Hunting Laser Bore Sighters

I owned 2 laser bore sighters, both were sold on the campfire. Not very useful/accurate for me. Best use was watching my dog chase the laser dot around the yard.

That was pretty much my experience too when I first got a laser boresighter, but the BTS software made a toy for playing with the dog into a valuable tool for setting up a new scope or realigning one taken off or adjusted. The free program produces an alignment target customized for my gun, sight, load, zero range and the distance I have available for sighting in.

I just thought I would let others know that if they have a laser boresighter, there's free software that makes it work a lot better.

I use the Leupold Zero Point Magnetic Boresighter too - http://www.leupold.com/tactical/pro...-point-magnetic-illuminated-boresighter/ . It has a lot of advantages over the laser in the chamber or in the barrel type boresighters. It's very light, small, has a built in grid, works even if the battery fails, and is very repeatable. I have a scope that I swap among several rifles, and I'm within an inch of being zeroed at 100 yards when I use it. The other advantage is if you do bang up your rifle/scope, you can put the boresighter on and then push on the scope, barrel, etcetera, and see if things are returning to zero or moving around...

A laser boresighter is supposed to be helpful when setting up a chronograph so you don't accidentally shoot it. Any one here use it for that?

Or you can not shoot your chrony the old fashioned way... Pull your bolt and boresight through your chronograph to your target, or read the manual that came with the chrony and they'll tell you how to do it. They tell you something along the lines of put some tape "X" inches above the center of the rods that hold your sky screens, then look through your scope at your target. Put the horizontal crosshair on the target where you want to hit and look to see if the horizontal crosshair is also on the tape. If not, move either the chrony or the target until everything is lined up. Of course the vertical crosshair should be centered between the rods when on target. "X" is usually the height of the horizontal crosshair above the center of the bore.

Maybe I'm just use to my SiteLite, but the steps needed to use the Leupold Zero Point Magnetic Boresighter seem complicated. Also steps 6 through 12 seem contrived as few shooters don't know how to zero-in once they are already at the shooting range.

Basically the Zero Point Magnetic Boresighter is designed to align the scope's line of sight to the barrel's bore centerline, but by sticking to the outside of the barrel. How well does that work with a tapered barrel?

The free BTS software goes one step beyond in that it allows you to align your gun and load to a specific zero range. Being you are aligning over a distance of 8 or more yards with a laser aligned to the actual centerline of the bore it seems inherently more accurate than something stuck on the end of the barrel.

It's not complicated - turn it on, stick it on the barrel so the little window facing the scope is about centered in the scope, look through the scope at the grid, adjust your crosshairs to be dead centered. This gets you on paper at 100 yards. Go shoot, get POI where you want it. Stick the boresighter back on, look at the grid where your crosshairs are, mark a little dot on the provided paper copies of the grid, and you now have your reference that you can use to field check your rifle with the boresighter. Takes less time than it took to type this.

If you can't figure out how to adjust your scope while at the shooting range, you probably can't get batteries in the laser boresighter, let alone read the instructions to use it...

The Zero Point goes on the end of your barrel, the not tapered part, not the side of your barrel, the tapered part...

Yes, the 12 step process I linked to before. The idea of a one shot zero seems a stretch. I've found that the first shot out of a cold and freshly oiled barrel is not representative of where a group of three to five rounds centers at.

With the SiteLite and BTS software I select the gun, sight, load, and the zero range and print out a custom alignment target for the distance I have available indoors. Pop the laser into the barrel and line it up with the spot on the target and adjust the scope to match the cross hairs on the target. Done this for a 200 yard zero and it was amazingly close at the range. Fire a group of three rounds and dial in the offset to zero. Then fire several more groups to make sure nothing moves. Easy, quick, and reliable. Show me the guy who would fire only one shot to sight-in before going on a hunt and I'll show you an inexperienced hunter.

Each rifle is different. I have several that were dead on at 100 yards, several others were within 2 inches, and one was about 4 inches off. I never said take just one shot, I said get the POI where you want it, meaning shoot enough shots that you truely know that you have the POI figured out. How many rifles have you tried your boresighter and procedure on? If you know about rifles you'll know that where the bore is pointing, and where the bullet hits, aren't necessarily going to be the same right? It's due to the fact that the barrel is whipping around in three dimensions as the bullet is going down the bore, and where the bore is pointed when the bullet exits is what counts. If you have a good load the bullet exits at hear the same time every shot, then the bore (actually the muzzle) is spatially in near the same place, and you'll get near the same POI, hence good groups centered around the same POI from shooting session to shooting session. So, regardless of boresighting method (and I wasn't dinging yours to start with) you're going to have to do some shooting. Use what works for you, but maybe keep an open mind in case something better comes along...

I agree that you never said take just one shot to sight-in. I got that from the marketing for the Zero Point Magnetic Boresighter. Glad to hear you don't buy the one shot sight-in hype. I also agree that no static sight-in technique can compensate for barrel whip, and that includes the Zero Point Magnetic Boresighter as well as all laser and optical boresighters.

I expect you're familiar with the concept of sight radius, which explains why the accuracy of iron sights increases with barrel length. The same principle is at work when boresighting. Any misalignment between the line of sight through the scope and the bore centerline is angular, and thus, increases in proportion to the distance over which it's measured.

The Zero Point Magnetic Boresighter sits at the end of the barrel some 18 to 24 inches from the objective lens of the scope. Whatever misalignment you could observe at that distance would be twice as large at twice the distance, but the physical design of the Zero Point Magnetic Boresighter doesn't allow for any extension. A high quality laser boresighter, such as the SiteLite, allows you to increase the alignment distance 10 to 100 times beyond what's possible with a device like the Zero Point Magnetic Boresighter, and thus, laser boresighters are inherently more accurate.

As most shooters know, to zero a gun at some distance the line of sight must converge with the bore centerline. The angle depends on the sight height, the trajectory of the load, and the zero distance. That's where the free BTS software comes in. It figures out that angle and prints an alignment target for whatever distance you specify. The BTS software works with any laser boresighter, but likely not with devices like the Zero Point Magnetic Boresighter.



I'm always open to new and better ways of doing things, but often new products are more marketing hype than substance. I learned a long time ago that understanding the underlying principles is the only way to figure out what's hype and what's real.

- So it's a good thing that the Leupold engineers took that into account and designed the optics on the Zero Point Magnetic Boresighter to give you an essentially infinity sight radius, right? The optics are like what's on red dot scopes, or holosights, where you can move it around a lot but things stay centered, and give you a long sight radius.




- Not quite correct, the LOS and bore centerline relationship don't necessarily correspond to POA and POI. POA and POI are determined by the relationship of where the scope is pointing and where the muzzle is pointing at the moment the bullet exits the muzzle. That's why no sighting technique where you don't fire rounds is only going to get you close, yours included. You didn't answer my question about how many rifles you've tried your product/procedure on. I'm guessing very few, or you'd realize what I'm getting at.

Oh, I just thought of another thing. How do you like those little "caliber specific o-rings" that you use on the spud? Bet they really contribute to the accuracy of the system, especially over time... I reload and shoot over 10 calibers, I have enough trouble remembering to bring the right ammo on a trip, let alone grab the right o-ring...

Yeah, okay, the end of the muzzle might not be square to the bore, so the Zero Point Magnetic Boresighter might have a problem, but wait, that's also part of why it has the infinity optics designed into it.

How much does the Sitelite weigh and measure, and how big are the target cards? From what I found on the web it's about 11 oz and L-10.5, W-4, H-3.5 inches. The target looks like it's about 11x6 1/2". I hunt places where weight and space are a premium, since everything goes in on my back. The Zero Point Magnetic Boresighter specs are: weight: 1-3/4 oz, dimensions: 4.2"L x 4.95"W x .06"D, and the target reference card is about 1x1". The card is actually too small for me, so I blew it up to about 3x3" on a copier and carry them in my wallet in the slip for my hunting license.

Then there's the disclaimer in the Sitelite manual - "The SL-1--/150/500 are delicate, precision instruments and must be handled with care."...

And finally, the Zero Point is about half the price of the entry model of the Sitelite.

But, again, not dinging your choice - do whatever works for you...

You're confusing infinite focus with infinite sight radius. The infinite focus allows you to focus on the gird pattern that's only inches away. Try focusing on some object that's right at the end of the muzzle and you'll see the difference. With optics the resolution of angular displacement is a function of power (magnification). An infinite sight radius would equate to infinite power and no scope offers that because such a device would be useless even if it could be built.

Basicly, the Zero Point Magnetic Boresighter is a magnetic mount optical collimator. Other than the compact size and low cost, it's nothing new.



Sorry, but if the sight is mounted above the barrel the LOS must converge with the centerline of the bore in order to zero any load some distance down range. I know about barrel whip, but unless you are using rubber barrels, it amounts to less than 1 MOA for any rifle worth taking on a hunt.

To zero something like a 25 WSSM at 200 yards you need about 4.6 MOA of convergence or more depending on sight height. Without knowing that angle all any boresighter can do is get you on the paper when mounting a different scope. The free BTS software solves that problem.



It's actually a very good system. You can test it yourself just by putting a rifle in a gun vise and putting the SiteLite in and then taping a target up some distance away and adjusting the target so the laser spot is over the X in the center of the target. Go back and take the Sitelite out and put it back in but trun it 90 degrees clockwise. Go back to the target and see if the laser still hits the X. If so, repeat for another 90 degrees and then another 90 degrees. If the laser always ends up over the X you know the boresighter is aligning to the centerline of the bore. I've used the same o-rings dozens of times betweens such calibration tests and as long as they are not showing wear the alignment of the SiteLite has been spot on. How do you self-test the Zero Point Magnetic Boresighter or do you just trust it to be right by blind faith?



If you read the reviews at the Cabela�s site you'll find that "firehunter79" contacted leupold when he couldn�t get it to work and was told by them that the Zero Point Magnetic Boresighter can't be used on any firearm with a flash hider. Likely because it must mount at a near perfect right angle to the bore's centerline. That matches other reviews I've read that say to carefully clean both the boresighter and the muzzle before using. From the reviews on Cabela's it looks like the biggest problem for the product is the lack of good instructions, which probably explains some of the 1 out of 5 ratings.



I agree that for use in the field the Zero Point Magnetic Boresighter is the way to go for quickly checking your scope to see if the zero has moved, but when it comes to setting up one of my rifles I'll be using the SiteLite. As usual the tool that works best in the shop may not be best in the field.

Okay, you win... We can take it offline, as the rest of the guys probably don't want to listen to us anymore.

I found a Guide to Boresighting at

www.twincityrodandgun.com/PDF%20files/GuidetoBoresighting.pdf

The guide covers optical and laser boresighters including magnetic mount optical. Page 8 says Note that axis of the bore and the axis of the collimator must be parallel. Therefore the face of the muzzle must be perpendicular to the bore.