Bore Sight Question

[Mike1647]

Mounted a Leupold Rifleman 3-9X40 scope on my Sport using Leupold riser mounts. When I tried to bore sight using a laser cartridge I cannot move the POI up far enough to line up the laser and the cross hairs. I was using a distance of about 50 yards. What am I doing wrong? Is the mount too tall? It measures 1" from the rail to the bottom of the scope tube.

 

[Rastoff]

Are you turning the adjustment the correct way? If the cross hairs are high, you should be turning the adjustment in the "up" direction. I know it sounds counter intuitive, but this is how a scope works when trying to line up a laser bore sight.

When making adjustments with a scope you're moving the point of impact, not the reticle. Think of it as though you're trying to move the laser, not the reticle.

 

[Westie1]

Did you verify that it's not a misaligned laser? it's real easy for those things to be just a little out of align, and that could result in you problem.

 

[Mike1647]

Yes the cross hairs were high and I was turning toward the "up" direction but ran out of adjustment before I was able to get it where it needed to be. I don't have another laser in 5.56 to compare to but I will try positioning it differently in the chamber.

 

[Westie1]

Try the old school way.Reset your scope. Separate the upper and lower. Remove the bcg. Balance the upper on some bags and without touching anything, look down through the barrel and then through the scope. As long as everything is on paper, you're good to go for final adjustments. Fire 1 round and see where it hits. Unless something is screwed up, it'll be on paper

Although meant for longer ranges, this video is real good.

[ame]https://www.youtube.com/watch?v=aDrrJA14wtg&t=3s[/ame]

 

[Rastoff]

Yes the cross hairs were high and I was turning toward the "up" direction but ran out of adjustment before I was able to get it where it needed to be.

OK, just wanted to be sure because I've seen this mistake before.

The next is to call Leupold. They are a great company, but you did buy a cheap scope. It's not uncommon for scopes at this price point to be out of alignment. Seriously, call Leupold, they will make this right or give you the help you need to get it right.

 

[bamashooter]

Here's how'd I deal with the laser and optic.

Lase the target at "about 50 yards" if the laser dot is visible. Mark the target where the beam hits.

From the same position as your firearm was, adjust the scope to your mark, circle, etc.

If the scope can't do a POA on the mark, something is likely out of whack.

If possible, I'd first do 25-30 yards and advance the distance from there.

Better than 50/50, the laser should at least get you on paper. Once in a blue moon, they do better than getting you on paper.

 

[Mike1647]

I took Westie1's advice and did it the old school way. This also showed that I did not have the scope true vertical/horizontal. I was able to get the POI pretty close. I hope to try it out soon and see how it does. As far as contacting Leupold, should the vertical adjustment end up at close to the limit of travel because even now the adjustment is pretty close to the end of range.

 

[MistWolf]

Center the windage dial first. If the windage is too far to one side, it will limit elevation travel.

 

[505Gibbs]

Generally, not always, the lower the price point of the scope the lower the internal adjustment range is - IMO.
I almost always use the Burris Signature rings to maximize my elevation range. Alternatively you can shim the rear of the scope for more elevation.

 

[C J]

Did you verify that it's not a misaligned laser? it's real easy for those things to be just a little out of align, and that could result in you problem.

Actually a bore laser can't be that far off. It won't shine down a bore and make a point down range if it's that far off. Some have to be adjusted to make them shine down the bore but they will just show up as blurred light patterns if they aren't shining directly down the bore.

BTW I would guess the sight is mounted too high on the OP's gun. For the record a 50 yard zero is too close IMO. Things may be much easier to work with at 100 yards and a .223. Zero at either 100 yards or 200 yards and compensate when aiming for shots at 50 yards when using a scope. A red dot is different of course.

 

[Rastoff]

I was able to get the POI pretty close.

The old school method is what I use and it works well. However, "pretty close" is not the goal. We're looking for perfect here.

As far as contacting Leupold, should the vertical adjustment end up at close to the limit of travel because even now the adjustment is pretty close to the end of range.

It doesn't matter the make, model or price range, no adjustment should be at or even close to its limit when zeroing a scope.

Call Leupold. The call is free and they will help you. They will likely replace the scope for free. They are good people and know what they're doing better than any of us: (800) 538-7653

 

[Mike1647]

I will be talking to Leupold tomorrow just to be sure. I gave about $200 for this scope and I don't really consider that a "cheap scope". I know there are much more pricey scopes out there and you do get what you pay for, but to me a cheap scope is a $30 Tasco at Walmart. Thanks for all the suggestions.

 

[jwk]

Dumb question while I see you talking about the laser and the crosshairs can you zero the rifle so that bullet holes in the paper are where you aimed? If yes no problem. If no then call Leupold. Also if the scope is moving when you dial it you may have a bad mount.

 

[Mike1647]

Very helpful guy at Leupold said that i was not using enough distance in my bore-sighting, at least 50 or better yet 100 yards is required. The scope/mount combo is fine for the AR. He also said that on some AR applications a 20MOA mount helps in this situation. Next weekend more work to be done.

 

[Rastoff]

Very helpful guy at Leupold said that i was not using enough distance in my bore-sighting, at least 50 or better yet 100 yards is required. The scope/mount combo is fine for the AR.

I'm glad you called. Any scope worth having on an AR should be able to be zeroed at 50 yards. This equates to zeroing at ~225 yards as well. Still, a 100 yard zero might be more suitable to this scope and mount combination.

He also said that on some AR applications a 20MOA mount helps in this situation. Next weekend more work to be done.

You shouldn't need a 20MOA mount for this application. The function of a 20MOA mount is to angle the scope down to allow more adjustment of the elevation. This is only ever needed for long range shooting i.e. greater than 1,000 yards.

This particular scope has 56MOA of elevation adjustment. This means that there is 28MOA of adjustment up or down. 1MOA at 50 yards is 1/2" so, this means the POI can be moved up 14" from zero. If mounted with quality rings (which you have), no scope should be further off than that regardless of price.

Further, if the POI is off by more than just a few inches with the elevation set to the middle, something is wrong with your scope.



I apologize for using the term "cheap" when talking about your scope. It's not a cheap scope in terms of quality. It is a quality scope. However, Leupold makes scopes from $230 to over $6K. In that range, you bought the lower end. Make no mistake, it's still a good scope and should work properly.

It's my belief that this will boil down to one of two things:

• Broken scope
• Improperly mounted

It's hard to mount the scope improperly when talking about a 1913 rail system (picatinny rail that all ARs have). So, I suspect you're doing everything right. It just happens that some scopes get knocked out of whack or are defective from the factory.


One last question; do you see the reticle move when you adjust it?

 

[Westie1]

I agree with Rastoff as to you don't need a 20MOA rail. With typical 55gr loads, you have enough scope adjustment for around 700yds. Problem is, they go subsonic at around 650. And once they go subsonic, accuracy goes out the window.

 

[Mike1647]

No apology needed, I bought what I believed to be the best scope that I could afford. Yes I did see it moving until I reached the end of adjustment travel. He gave the 20 MOA suggestion as an "if all else fails" kind of thing.

 

[Racer X]

You can also get that 20 MOA using Burris Signature Zee rings with a -10 insert up front, and a +10 in the back.

 

[Westie1]

Best thing to do now is to shoot it and see where is actually prints on paper. You'll want to do the shooting off of some type of rest. That way the human element is removed. If you need to use most or all of the adjustments, there's an issue with the base/rings or the scope. Contact Leupold and get them to check the mount and scope. Things do come out of the factory defective every once in a while. i know of a report of a RPR that broke on the 2nd shot. It does happen.