Center a scope?

MD

MD

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I was given a HVA 270 rifle with a 6X Leupold scope mounted on it.

The previous owner said he was uncertain if the rifle was sighted in as he had never shot it.

I don't want to go to the range to find out that it has its windage or elevation adjustments maxed out.

How can I centre the scope?

I read somewhere that you wind the adjustment all the way to one side, then click the opposite way counting clicks, the divide that number in half and move that many clicks back.

Correct?
 
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Why would you skrew up something that ain't proofed tuh be skrewed up?
Set a target at 25 yards and put a hole in it.
Adjust scope to proper windage and move out.

Or dew like them old folk that don't beleaf in bore sighters and pull the bolt,
line the bore up on something looking down the bore and then mewf yer eye
up to the scope and see if'n yer in the bawlpark>>>>>?

Nawt horriblie scientifically ?
 
What you describe is correct way to centre crosshairs in the scope - usually done as part of scope mounting process where scope mount bases are being shimmed / soldered into place. I suspect that you would be much better off by bore sighting the old school way - make some sort of holder for rifle (notches cut into a cardboard box on opposite sides work fine). Remove bolt and peer down bore. Punch out a primer from a fired cartridge and insert into bore to be more precise, else just use the bore. Align bore with some small object plus or minus 25 yards away (i.e. through your window??). Move box, shim as necessary to get bore exactly aligned with your subject. Then compare to what your crosshairs are aimed at. The trick is to align the bore and then completely let go of rifle so it does not move, then see where crosshairs are aimed. Left / Right needs to be very close. Up/Down is nice to have close to right on at about 25 yards. If done as above, you will be on 12"x12" paper at 100 yards. Note that for this exercise you will be moving the crosshairs on the target, not the bullet holes, therefore the scope adjustment directions will be backwards - if your crosshairs are left of your bore alignment, you will turn your turret adjustments to the right - the "bullet hole" (bore alignment) is going to stay in same place, you will be moving where the crosshairs point...
 
Hey there, 'Looky - just saw your post after I put up mine... I am very comfortably situated among that group of "old folk that don't beleaf in bore sighters". Sometimes old school is just simpler, easier and cheaper... :)
 
I tried Babelfish and Bing and a couple of other translation programs and couldn't translate Kamlooky's message. Maybe I have to find a site that translate Jelvish.

Anyway, back to the subject at hand:

I have done bore sighting at the range and indeed at home with the cardboard box method.

My concern was, as I explained, that I am uncertain if I can trust the rifle scope to have enough adjustments left in case it has been on several rifles over its lifetime.


I'll try the box method at home before I even go to the range. have to cut up another one I guess, lost my old one.
 
Try placing a small mirror in front of the objective lense.
That there is the front one opposite the eye lense.
If you get the mirror placed just right with the right amount of light
let in, you will see an image reflection of the cross hair on the mirror.
You may have to tinker with this a bit to see if it will werkie fer yah.
If they are near one n'uther, you should be good to go.......as in A-Oh-Kay...........:wave:
 
Got that loud and clear Kamlooky.

I've done that with unmounted scopes in the bathroom mirror, but don't want to rip this scope off the gun.
 
I'm starting to think MD knows more than some people replying are giving him credit for. I'm going to take a stab at what he's looking for. And that is you're wondering if the mounting itself is as centered as possible?

So yes, if you count all the clicks in its range, and divide by zero (and subsequently turn that many clicks from one end) that will mechanically center your erector inside the tube of the scope. Ultimately you would want your windage to zero as close to center as possible and for your elevation to zero a little on the low side (how low depends on how far you want to shoot most often) That way you're sure to be using the middle, and optically best portion of the glass at your ideal range.

A word of caution. No matter how many rifles that scope has been on... it's not going to change where the mechanical center is. The tolerances and manufacturing process of the manufacturer are the only influence on that.

And if you do find it's mounted a bit skewed on your rifle, you then have to have a plan to fix that rather than turning the turrets of the scope. That would be an actual mounting issue, and would most likely require a gunsmith. Point of the story, if the scope doesn't zero where you want it to, it's a mounting issue.
 
If you just want to get your windage centered for the purpose of mounting with your windage adjustable mounts or perhaps because you're shimming for elevation there's a quick and easy method. Turn the adjustment all the way to one side and count the full turns to the other side. Go back half. It will likely be close to 6 turns so go back three. No need to count clicks. Besides, it's easier to count to 6 than to 360 and back 180.

There is usually a small difference between the mechanical and the optical center but of enough to matter in real life.
 
If I read the OP correctly then his post has nothing to do with sighting in - whether it be bore-sighting or using some mechanical/electronic aid. What the OP is concerned about is the mechanical centre of the scope - the way to do that is to go through the full range of each turret counting each click - lets say that elevation is 84 clicks just to give us a number - and divide that number by 2 so, in our elevation example the mechanical centre is 84/2 = 42. Do the same with windage and you are now set at mechanical centre.
 
Yes, FF57, Dogleg and Tomochan, you read my query correctly and thank you very much for your advice.

Yes, I know how to sight in a rifle. I was concerned about the mechanical center of the scope.

Thanks again for your positive advice.
 
"So yes, if you count all the clicks in its range, and divide by zero (and subsequently turn that many clicks from one end) that will mechanically center your erector inside the tube of the scope."

If you "divide by 0" you will be turning an infinite number of clicks.
 
stampede said:
"So yes, if you count all the clicks in its range, and divide by zero (and subsequently turn that many clicks from one end) that will mechanically center your erector inside the tube of the scope."

If you "divide by 0" you will be turning an infinite number of clicks.
Click to expand...

Whoa! Good catch! Had zero on the mind. Gotta keep calculus away from the range.
 
To Op - you might want to re-read the first sentence in reply #3... Also, the hand mirror trick gets you to the same place without cranking on turrets - if the reticle and its reflection are close to each other, you are optically entered.
 
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