Optically centering scope HELP!

[cootertwo]

OK, done lot's of reading, watching video's etc. I have a new scope, no name bashing here. When I use either the mirror, or the "V" block method, to bring it center, my vertical is almost maxed, and the windage at least 3/4 maxed. Is this just a cheap/bad scope, or rather common? Also I think it better to center the scope with the counting clicks method, then mounting and sighting in, rather than leave it "optically" centered, with hardly no adjustments left. RIGHT ??

[mobilehomer]

I prefer the counting clicks method. It is also the one recommended by many scope makers, including Leapers.

[cootertwo]

So advice to set mechanically optically centered, then sight in? Just curious?

[Taso1000]

The v-block method should be the most exact to optical center.  The mirror method can be skewed a bit off if the objective bell or trim is not true to the optic path.

I assume staying close to the mechanical center is best because the adjustments don't work as expected at the extremes of the adjustment ranges.

This web page shows this issue:

https://www.airgunsofarizona.com/blog/2010/04/how-scopes-really-work-and-what-not-to.html

Taso

[mobilehomer]

Yep.  And depending how much it needs, you might need to adjust other things before the scope turrets. I sight in at 20 yards initially. If my break barrel is off by more than an inch or so, I bend the barrel as close to POA as possible before twisting turrets. My non-bendable guns, a 2400KT and Maximus Hunter were almost perfect. You can use adjustable rings, or shims for either barrel type.

[Roadworthy]

Counting clicks is best mechanically for the scope.  It should put things very near the center of their physical travel.  At this point it should be close to optical center but not necessarily quite there.  This is generally the point from which I start to sight in. 

If you need to start approaching a mechanical limit to sight in your gun you have a scope problem, a gun problem, or a problem with your mounts.  Sometimes the mounts are simply installed incorrectly.  Another scope or another gun is a big help when you start troubleshooting.  All brand new scopes are not necessarily perfect out of the box and neither are brand new guns or mounts.

[nced]

OK, done lot's of reading, watching video's etc. I have a new scope, no name bashing here. When I use either the mirror, or the "V" block method, to bring it center, my vertical is almost maxed, and the windage at least 3/4 maxed. Is this just a cheap/bad scope, or rather common? Also I think it better to center the scope with the counting clicks method, then mounting and sighting in, rather than leave it "optically" centered, with hardly no adjustments left. RIGHT ??

Today I had a discussion with the Hawke "tech guru" concerning this very question and he mentioned that "spinning in vees" is the best method of optical centering. I was told that counting clicks & dividing by two wasn't a reliable method of centering because "clicks" really don't have a definite stop. The reticle stops when the erector runs out of space, not necessarily at the end of the clicks. He also mentioned that Hawke has done testing using the "mirror method" and found that the centering can be off by as much as 10moa being that the centering is dependent on the squareness of the objective lens to the scope tube.

Scopes are normally optically centered from the factory so the first thing I do is to check the scope reticle alignment using my bathroom mirror before touching the turrets. The reflection of the reticles in the mirror for the three Hawkes I own with 50mm AOs (AirMax, Vantage and Panorama) and the 3-12x50 Aeon all had the reticles centered on the reflection in the mirror within a couple clicks straight from the box. If the "straight from the box scope" reticle is centered on the reflection in the mirror within a couple clicks I use the "mirror method" if the reticle needs to be re-centered.  I also set the turret numbers to zero at the optically centered position so I can always return to the "factory setting" if needed. Years ago I had a 3-12x40 Hawke Airmax AO and evidently the AO wasn't square with the scope tube because I tried centering the reticle using the mirror, count divide by two, and spin in vees. LOL.....there wasn't an agreement between any of the methods used and the centered reticle was even in different quadrants of the view in the mirror. 

[mpbby]

IMHO, cootertoo, this new scope has a problem.  What you described doesn't make sense and you should contact the vendor regarding the warranty proceedings.

[TwiceHorn]

I may be barking at the moon here, but counting clicks or turret rotations is what I have always called "mechanical centering," whereas the mirror or v-block thing is optically centering.  You can be in the middle of the travel of the turrets and nowhere near optically centered, as demonstrated by OP.

It seems the two types of centering address two different problems:  mechanical the problem associated with turrets and the erector tube at the limits of its travel, while optical is the alignment between the scope center or optical axis and the bore.  The two problems become related when the optical axis is sufficiently misaligned from the bore that adjustments to the extremes of turret travel are necessary for zeroing.  Otherwise, they are unrelated.

[nced]

I may be barking at the moon here, but counting clicks or turret rotations is what I have always called "mechanical centering," whereas the mirror or v-block thing is optically centering.  You can be in the middle of the travel of the turrets and nowhere near optically centered, as demonstrated by OP.

It seems the two types of centering address two different problems:  mechanical the problem associated with turrets and the erector tube at the limits of its travel, while optical is the alignment between the scope center or optical axis and the bore.  The two problems become related when the optical axis is sufficiently misaligned from the bore that adjustments to the extremes of turret travel are necessary for zeroing.  Otherwise, they are unrelated.

Well....new scopes are normally optically centered from the factory. If the reflection in the mirror matches the factory reticle centering within a few clicks I figure that it's "close enough". Funny thing is that unless the scope is clamped in an adjustable mount  (or bending the barrel) and zero'd without turning the turrets, optical or mechanical centering means very little!

[cootertwo]

Thanks for all the reply's. I'm still tinkering. BTW, I'm also into RC air craft, and found this prop balancer to be very useful in doing the "V" block method of centering the scope!
https://www.horizonhobby.com/tru-spin-prop-balancer-dub499
I'm going to start from scratch, mounting my scope, as I didn't use a level, etc. etc. Also have a new Huma regulator to install in my Wildcat, and a new scope rail coming in the mail. Then I'll experiment some more with a few different scopes, to for giggles, and to see how much difference there is between them.

[bandg]

As NCED noted, either optically or mechanically centering is not helpful unless you have adjustable mounts because you will still have to change the turrets to zero the gun (unless you bend the barrel and I don't do that unless absolutely necessary).  I use SportsMatch fully adjustable mounts on many guns for this reason.  Yes, they are expensive but they are rock solid when locked and they allow you to "center" the scope with your method of choice and then zero the gun using the mount.

[nced]

As NCED noted, either optically or mechanically centering is not helpful unless you have adjustable mounts because you will still have to change the turrets to zero the gun (unless you bend the barrel and I don't do that unless absolutely necessary).  I use SportsMatch fully adjustable mounts on many guns for this reason.  Yes, they are expensive but they are rock solid when locked and they allow you to "center" the scope with your method of choice and then zero the gun using the mount.

I guess I do take some exception to the "not bending a barrel unless absolutely necessary". Years ago I used a couple different adjustable mounts and found that they weren't worth the hassle. One of the adjust-ables was a RWS C mount like this........

Those mounts of a couple decades ago required that the scope be first mounted, shoot a group to determine the poi, then remove the scope to make slight adjustments by twisting the "height adjusting screws" then locking the setting in place with tiny set screws. If more adjustment is needed then the scope was removed from the mount base and the whole process was repeated till the poi was on the aim point. LOL....after a few hours setting up my adjustable mount my springer still "shot loose" after a couple months use. Anywhoo......I found it simpler and more permanent to simply bend my barrel!

LOL....barrels are commonly bent at the factory...........

Supposedly this match pistol was very accurate even though the barrel was crooked........


Anywhoo....whatever "trips yer trigger" is fine with me but I prefer to simply bend my airgun barrels rather than mess with adjustables.

[bandg]

No offense intended and I've certainly read of others bending barrels quite successfully.  But I've had excellent results from the SportsMatch fully adjustable rings.  They allow the user to get within just a few clicks of desired zero and then lock firmly with no detectable movement.  The scope does not have to be removed-all adjustments are easily accessed on the base of the mounts.  It does take a few tries to get them set just right but it isn't that difficult and the most important thing to me is that they hold zero very well once locked.  I have a couple of sets on guns now and just received another set not yet mounted.  They have held zero on a Diana 460 so it seems they should work for most any springer.