Scope zeroing issues - is my receiver drilled wrong or barrel misaligned?

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machohugeaxe

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Never had an issue like this before but this was a combination of a new barreled action and a new scope at the same time so took me a while to figure out whats going on.
Got a bergara b14r barreled action and a cheap vortex crossfire II scope because I was too lazy to remove scopes from other rifles. Got a 20 moa rail and 0 moa rail handy.
Installed correctly, torqued correctly, checked that there is no space between receiver and rail.

Took it to the range and tried sighting at various distances, couldn't even zero at 10 yards, it was shooting high and right, ran out of both elevation and windage.

So i took it home and started experimenting. First I started by using the mirror trick to take scope back to mechanical zero.

Facts:
  • Put scope on another rifle and used a laser bore sight and it was easy to get the crosshair to line up with laser at 10 yards
  • Put scope back on bergara and had similar issues again, point of impact (of the laser) was high and right compared to reticle.
  • Put a vortex venom sighted on another rifle on the bergara and noticed that the point of impact (of the laser) was way high and right compared to the reticle. Was able to get it to zero but it was at the bottom of the elevation range. A good amount of adjusting windage to the left as well. The venom has higher adjustment range than the crossfire II
  • Tried both 0 and 20 MOA rails thinking maybe the rail could be the issue but doesn't seem like it, both experience the same problem.

Not sure if this is the right place to post since if I'm right then its not an optics problem. If its the receiver drilling or barrel alignment, is there anything I can do about it? or am I resigned to putting a scope with high adjustment range on it?

Thanks


Edit:

Here is the setup and the issue I'm describing with the scope

Mount - 0 MOA 1 piece

q0aRH9r.jpg

Scope
LuvdEvL.jpg


Scope bore sighting. Keep in mind this is 10 yards so my goal is to have the reticle to be a bit higher than the laser point. Magnification is at 6 i believe.


When scope is mounted after going back to mechanical zero. The black circle is about 1 inch in diameter
EUsbH5O.jpg


Now if I dial elevation ALL THE WAY DOWN. Even though the windage hasn't been touched from mechanical zero, I CANNOT TURN IT AT ALL
SEabqH8.jpg



Now if I reset both windage and elevation, then turn windage ALL THE WAY LEFT. Now I can't turn Elevation turret AT ALL.
drMapaF.jpg


Finally, I reset, and turn windage and elevation alternating, a bit at a time

ErGhtzL.jpg



Note this is close to what I want, but BOTH ELEVATION AND WINDAGE ARE MAXED OUT, I can't go anymore to the left or down.
 
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I am not sure that I follow all of your dilemma - but I would wonder why you are using a 20 MOA rail, if you are sighting in at 10 yards (30 feet)? From your post, you explain bullets hitting high and right, then talk about a scope "point of aim" being high and right - that would mean that bullets will hit low and left of point of aim - bullets and "point of aim" go opposite to each other, usually - they are not the same??

FYI - that "mirror trick" to mechanically centre the scope - is often (mostly) used when you are altering the bases or mounting system to get the scope aligned to the bullet flight - typical installation of simply screwing down that rail is going to get you so many clicks up or down and left or right from that mechanical zero, to be "sighted in".
 
Sorry yes I mean point of impact, but I was using a laser so I used the wrong term, will edit to be point of impact. Laser was high and right, bullets were hitting high and right, both relative to the reticle.
I was doing at 10 yards because I couldn't even find where the impact was at 25, and further, it was off the cardboard.

Previous owner said he had no issues sighting to 400 yards even so I wonder if its my user error somehow or whether I've done something to it. Never had any issues with other rifles and scopes though... I'm out of ideas.

Potashminer said:
I am not sure that I follow all of your dilemma - but I would wonder why you are using a 20 MOA rail, if you are sighting in at 10 yards (30 feet)? From your post, you explain bullets hitting high and right, then talk about a scope "point of aim" being high and right - that would mean that bullets will hit low and left of point of aim - bullets and "point of aim" go opposite to each other, usually - they are not the same??

FYI - that "mirror trick" to mechanically centre the scope - is often (mostly) used when you are altering the bases or mounting system to get the scope aligned to the bullet flight - typical installation of simply screwing down that rail is going to get you so many clicks up or down and left or right from that mechanical zero, to be "sighted in".
Click to expand...
 
I have installed perhaps a dozen scopes on my rifles in past several years, and have not come across what you describe - even on receivers that I drilled and tapped. About "worst" was attempting to install a side mount on a Cooey 60 - barrel and scope were visually pointed to different places - I had to install significant shim between receiver and side mount base to get the two pointed the same way.

I would think any error in drill and tap would result in left-right error - mostly I saw that here when I lapped the ring saddles and found very uneven - tilted - lapping patterns - so the scope mount holes were not straight in line - rings were tilted (twisted) to each other - I don't think there is more than one or two one piece rails here - most all are two piece bases - so three or four mounting holes needed. I suppose is possible to have a bore and chamber not centered within a barrel - I cut off a Remington 788 barrel and the bore hole is visibly not in centre of the barrel - so even if outside of barrel looks straight to receiver, the bore may not be. Is a thing, I think - muzzle condition and maybe last caliber length of the barrel decide where the bullet is going - meaning most "bore sighting" tools only going to get you "close" - not exact. Has been my practice to install a scope - use about 24" x 24" cardboard at about 25 yards - never did not "catch" bullet holes - then walk them in to be centered left /right and a bit low - almost always very close to slightly high at 100 yards - maybe a click or two for windage. Has been my experience to shoot "groups" - say three shots - then measure and adjust scope to move the centre of that group - can "waste" a lot of ammo trying to sight in one shot at a time, if the outfit is shooting 4" groups at distance of choice.

Before going with "one shot then adjust scope" - is useful to fire at least three shots aiming at same point - say 25 yards - most rifles here will create three lobbed overlapping holes, or at least touching or very close to touching - if they do not, is a sign that something else very wrong with shooter, scope, mounts, rifle or ammo - would be waste of time to proceed to try to "sight in" until those other errors are corrected.
 
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No mention of rings - Mismatched rings could be an issue. Or rings that aren't matched to the base.

OP, how far high and right are we talking? And, photos of the setup would really help.
 
"matching" - "mis-matching" - how are rings matched to bases?? I have a set on Conetrol rings - instructions say that ring caps were machined with the saddles - so they will go together either way, but only one way is "matching" - how is that done with rings to bases - if the rings and bases not sold together??

I have had about opposite to "matching" - so would be different results, which way ring or base installed - turn them end for end and get difference. They were not marked which way was "correct" to install.
 
I experimented some with 0 moa (dnz 1 piece mount/rings), and found that for this scope, the elevation and windage "maximums" are not fixed?? Maybe this is common knowledge but it seems like when I maxed out on elevation for example, the windage will not turn, now if I backed out of the elevation some, then windage is able to be adjusted again. I think I was so confused yesterday because the scope started out near the maximum windage and elevation, and with the maximums keep changing, I got turned around.

This is the cheapest scope I own, and I haven't ran into this issue before because I haven't needed to be near the maximum adjustments. Is this pretty common? I was able to get the point of aim close to the laser point by adjusting both elevation and windage small bits alternating, rather than either all together.

Now I'm thinking its the scope that isn't well "centered" if that makes sense. Although I did put it on another rifle and the issue wasn't as pronounced... maybe its a combination of more than 1 problem.

i.e. when I reset the scope to the middle of the range, and then throw it on the rifle, the point of impact ends up really high and right. Next I probably adjusted windage all the way to the left and left no room for the elevation to move? This time I adjusted both, taking turns, in small amounts and was able to get it to be much closer.

I'm not knowledgeable about this field to know, is this how some scopes just work? or should I send it in for warranty?
 
I do not know how modern scopes are made, but think like the scope body is a larger diameter tube and the reticle is in a smaller diameter tube, inside the big one. A gimble or similar at the front of small diameter tube and the turrets and bias spring acting near the rear end of the small tube. When at mechanical dead centre with small tube - is much left to right or up and down adjustment available. Now force the small tube against top or bottom of the big diameter tube - or against left or right - by "maxing out" turret adjustments - can not move at right angles, or can not move very far, because the two tubes are hitting (or close to hitting) to each other.

Might have been more of an issue in old days when image stayed still and reticle moved - could end up with scope "sighted in" but scope reticle crosshairs noticeably not even close to centre of the view. I think I read that Bill Weaver one of the first to figure out how to keep the cross hairs within middle of the image - I do not know how he did that. I did own elderly Lyman "Perma Centre" scope which apparently made a "big deal" out of keeping the cross hairs in centre of the image.

Versus even older design where there were no turrets on scope at all - nothing internally adjustable - all "sighting in" was done by fitting the bases to the rifle and by external windage and elevation adjustment - is an older german made Hensoldt scope here - no windage turret - windage was meant to be adjusted in the mounting system that was used with it.

Sort of sounds like you are "bottoming out" with inner tube at 10:30 on larger tube (or 1:30, or 4:30 or 7:30) - that might be because your mounting installation requires more adjustment than that scope has. Or your bore is not straight with your receiver. Or something wrong with your installation. Or the bases. Or the rings. Or the receiver contour grind. Or the receiver mounting holes alignment. Or a combination of more than one of those. Your barrel is going to throw bullets to a particular place. Where that place is, has nothing to do with the scope installation - to be "sighted in", is to have your scope reticle pointed at that place where the bullets will go.

Depending what it is and how bad is your issue, can have things like damage to muzzle crown throwing bullets left, right, up or down from theory bore centre line. Bullet is going to travel in a curve - due to gravity - so should be close left to right, until / unless wind gets that bullet, but almost always that bullet going to drop away from the theory bore line. Is why I fundamentally do not trust "bore sighting" tools that align to the bore - I do not understand that they can do anything more than I can do by peering down that bore to align it at a target - they might get you "close"- like within several inches - but you really need to fire bullets on target to know whether you are "sighted in" or not.
 
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machohugeaxe said:
... Maybe this is common knowledge but it seems like when I maxed out on elevation for example, the windage will not turn, now if I backed out of the elevation some, then windage is able to be adjusted again. I think I was so confused yesterday because the scope started out near the maximum windage and elevation, and with the maximums keep changing, I got turned around....
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Sounds like poor quality scope turrets, that's all. Count the clicks in the total adjustment range to make sure you're getting as much adjustment as you should be able to with that scope. If not, warranty for sure.

Please post photos of your scope/rings/base/receiver, it may help.
 
I’ve have a rifle that a scope will run out of windage adjustment, the mount holes are not drilled true. It is possible to shim the bases to compensate but I decided to go with a leupold base with windage adjustments.
 
Standardvel makes a good point. When there are no issues with the scope and the rings are good, there remains the possibility that the receiver holes are not as they should be.

Another alternative is perhaps a little more disconcerting. Barrels are sometimes out of line in the sense that they are mounted so that they are not "pointing" where they should be, that they are improperly aligned with the receiver.
 
Standardvel said:
I’ve have a rifle that a scope will run out of windage adjustment, the mount holes are not drilled true. It is possible to shim the bases to compensate but I decided to go with a leupold base with windage adjustments.
Click to expand...

grauhanen said:
Standardvel makes a good point. When there are no issues with the scope and the rings are good, there remains the possibility that the receiver holes are not as they should be.

Another alternative is perhaps a little more disconcerting. Barrels are sometimes out of line in the sense that they are mounted so that they are not "pointing" where they should be, that they are improperly aligned with the receiver.
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Both good points here. OP, in one of your posts you stated that the bullets and the laser were both pointing to the same place. If that's the case, just center the scope and buy a set of Burris Signature Zee rings with the different sized inserts and use these to get the point of aim on target and fine tune afterwards.

I have a Remington 7600 that I had to do that as I ran out of elevation on both of 2 scopes that were known to be fine. In my case it was either the receiver, the mounts or the rings that was the problem. The Burris rings solved the problem.
 
machohugeaxe said:
...Previous owner said he had no issues sighting to 400 yards even so I wonder if its my user error somehow or whether I've done something to it...
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Unless you have some reason to doubt his word, you're right, there's got to be something going on with your mount and/or scope.
 
alpining said:
Unless you have some reason to doubt his word, you're right, there's got to be something going on with your mount and/or scope.
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Yea no reason to doubt. Like I said I believe the confusion has to do with the scope's limitations of windage/elevation adjustments when either one is near the maximum adjustment. Its just so weird to me that once I can't turn the elevation turret anymore, if I reverse the windage turret some, I can then turn the elevation further.

I'll post some pictures as well later
 
machohugeaxe said:
Yea no reason to doubt. Like I said I believe the confusion has to do with the scope's limitations of windage/elevation adjustments when either one is near the maximum adjustment. Its just so weird to me that once I can't turn the elevation turret anymore, if I reverse the windage turret some, I can then turn the elevation further.

I'll post some pictures as well later
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They bind internally on some scopes. I have had it happen with a few over the years. - dan
 
Quite normal not to be able to zero in at 10 yards. You can never zero in an AR at that distance because the scope is usually sitting on a cantilever mount and therefore much higher than the barrel. Same with my Bushnell laser bore sighter. The scope has to be low enough to be able to zero in at a short distance.

Would be nice to see some pictures of what you are doing actually.

Also, put the ring bases on first and see if the scope is actually sitting true in them before putting the top cover of the scope rings on.
 
I posted some pictures in the original post. If there is a cant it its because of me holding my camera... taking a picture through a scope is harder than I thought.

The final picture is close to what I want but both elevation and windage have been pushed as far as I can at that point, and I had take a stepwise approach to do each in an alternating manner. If I push one to the max first, I can't turn the other one at all.

Do you guys think this should go to warranty?
 
To quote from what you added on Post #1 - "so my goal is to have the reticle to be a bit higher than the laser point" - I think you have that backward - if you want to be sighted in very long way away, you would need the cross hairs to be BELOW the laser point at a short distance - if you believe that laser point accurately reflects where the bullets will go. I think that if you are looking through your scope against a laser dot on the wall, all the scope directions will be backwards - up is down, left is right - for where the bullet will go compared to where the reticle is pointing.
 
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