Home Forums Hunting & Shooting Ask The Gunwriters Bore sighters

Can someone recommend a reasonably price one ,that you can use from 17 cal. and up and works in AR's also . Thank you

I have an old Bushnell, gets me on paper at a hundred, but won’t work on my two AR’s. I sighted one in today at 25 yds, then moved back to a hundred.

I have a cheap BSA bore sighter. It works well enough to get on paper at 100 yds.

https://www.sportsmansguide.com/product/index/bsa-boresighter-kit?a=1174794

I've had two: a Bushnell years ago and a Leupold for the last few years. Both have given about a 50/50 chance of getting on paper at 100 yards. Much better at twenty-five. With a bolt-action rifle, bore sighting works about as well. There are probably better units out there than what I've used.

I have the BSA set as well. Always gets me on paper at 50 yards, might work at 100 but I start at 50..

One thing I've pointed out before in a few places is that ANY bore-sighter (collimator) needs to be "sighted-in." You do this by mounting it on an already sighted-in rifle (or preferably, several) and see where the scope's reticle is on the collimator screen.

It will NOT be in the same place for all rifles, due to a couple of factors, but will usually be in a general area somewhere AROUND the center of the screen. The middle of that area is where you need to move the scope reticle to have a good chance of bullets landing close to center on a target at 100 yards.

Some collimators can even be adjusted so the reticle of a sighted-in rifle is centered in the collimator screen, but tend to be more expensive, so may not meet Longbow's definition of "reasonably priced."

Collimators that attach with a magnet, rather than metal "spuds" inserted in the to muzzle, are more versatile and usually less expensive, but also tend to be less accurate, because they depend on the squareness of the muzzle, rather than bore itself. But they can used on just about any rifle--or even shotgun slug barrels.

Mine's a BSA I actually got by winning Penguin's You Pick 'Em football pool one year. It works. All these are to do is get you on the paper. In no way is your gun ready to go hunting after bore sighting. The arbor set that came with the gun covers everything from .17 up to .50 caliber. When I worked at the rifle range many years ago, they ran 4 of the Bushnell boresighters. I never saw it done, but I know they calibrated them before putting them into use, and it did make a difference. We never had a gun not be centered on the paper at 50 yards after the first shot, assuming the shooter had decent shooting skills. My BSA seems to be about an inch low and to the right at 50 yards, so I compensate for it slightly when I set the crosshairs before shooting.

Never got into the collimator idea, mostly because a visual thru the bore in comparison to the crosshairs/peeps on target does the trick most days. Some guns don't let one do that of course, but that's why the 25 yard line was invented maybe?

I inherited one from my father. I tried it a few times. It wasn't any more effective than a 25yd dot on cardboard, then a target at 100 as far as actual shots fired to get on paper. Maybe I should what Mule Deer suggests, but I find it just as easy to shoot at a close target once, adjust scope, and go to 100.

These threads always question the value of a collimator--though they're almost always called "bore-sighters."

I have also pointed out before that their best use is not in getting sighted-in, but in making sure a scope is properly aligned with the bore during mounting. This prevents all sorts of problems, including erratic adjustments.

I've never felt that one could saved me a single round, nor a minute of my time getting a rifle zeroed. With a bolt rifle I simply bore sight at 50 yards and then fire one shot at 50. I'm usually within 2" then I fine tune and shoot shot #2 at 100 and fine tune again. Shot #3 is zeroed. I've never found a bore sight tool that could get the 1st shot any closer.

With a rifle that I can't bore sight easily I just make sure I use a target big enough to ensure that I hit paper with shot #1. It doesn't really matter if the 1st shot is 10" or 1" from zero. As long as you have a hole in the paper it is simply a matter of adjusting the scope the correct amount.

+1 . Mine has gotten me on the paper at 100 yards 100% over 15 years.

It has the added benefit that if you take a measurement of the deflection after you've got it zeroed, you can use that for comparison later. This answers the question: did I knock the scope off kilter in transport?

A pc of old brass with the primer knocked out then inserted in the chamber works well on bolt guns.
I like using those orange or green target dots so it's easier to see them.

I have this one also, and it has always worked for 25 yards, which is where I always start anyway. I have had it work at a 100, but since I don't start that that distance, I don't know how reliable it would be.

I don't ever use one. If it's a rifle I can't look through the bore on, like an M1 or a lever, I just shoot at 25yds & adjust.
With bolt actions I remove the bolt and sight down the bore. ARs, just remove the upper from the lower and remove the BCG and do the same thing. With a steady rest, it works very well. Just remember to add elevation.

What's wrong with the laser type that sticks in the end of the barrel? I've had a Cabela's branded one for years. It has different plastic bushings so it fits snug in different bores. I usually stick it in, adjust scope, pull it out and reinsert it, adjust again if needed. Seems to work fine on every gun I've used it on.

Nothing. There's always more than one way to skin a cat.

I use a Bushnell magnetic boresighter, after mounting a scope. Boresighters put you in the ballpark (on paper). Follow the instructions and you should find bullet holes at 25 yd. I have a wooden straight edge that I hold against the scope to rough align the boresighter to my scope. How many times have you watched someone struggle with his rifle at the range, trying to find a solitary bullet hole? Take pity on them and help, if you can. I use this particular one because it is small, portable and can be used with any action type.



I used to harmonize F104 and F5 aircraft 20mm guns. The 104 was done at a 25 yd butt. Harmonizing is actually matching the gun sight with the gun because the HUD isn't attached directly to the gun itself. The a/c was jacked and 25 rds was fired into a backstop. Whenever we had a new technician on the crew, he would get to sit in the cockpit and squeeze the trigger. We always told him, "Don't forget to lift your feet before you squeeze the trigger!" There was no need to do this, but that started years ago as a joke and people just kept saying it.

F5s were done differently, using a 1000 inch white board and bore sighter. As you can imagine, it was quicker, easier to fix SA sights.

Here's an older pic of some RCAF armourers harmonizing the 50 cal guns on an F86. Look closely and you can see the a/c was jacked to disable the weight on wheels switch. I can't find any CF5 or CF104 harm photos.

Interesting this topic came up. I have a Bushnell that I’ve been using for years. The spuds are about done. Can you buy replacements .
Or is it time for a new one. Hasbeen

So a solid rest is important, even with aircraft.

It all comes down to individual preference really. However, I will say that after several decades of trying to mount scopes without my BSA bore sighter, I found that it simplified the process.

25 yard shots will get you your windage adjustment up to a point, but it will not get you elevation.

The BSA bore sighter I have has payed for itself many, many times over in saved ammunition, and it's answered a lot of questions along the way.