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Old June 14, 2018, 04:21 PM   #1
tpcollins
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Question about the spring and erector inside a scope

On a scope with CCW turrets, up elevation moves the erector up and right windage moves it to the right. But in order for the poi to do so, the crosshair needs to go in the opposite direction to accomplish that.

Is this because the image is upside down inside the erector tube and up is actually down and right is actually left when it gets turned back right side up at the ocular? Thanks.
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Old June 14, 2018, 06:52 PM   #2
Art Eatman
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"Up" moves the point of impact up, yeah. Doesn't that merely mean that the issue is that of labelling? "Turn it this way to get this result."

(I've never really thought about it before. Just followed directions. )
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Old June 14, 2018, 07:57 PM   #3
RC20
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Directions? What are those?
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Old June 14, 2018, 08:56 PM   #4
J.G. Terry
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Do What?

It's like the same as moving the front sight. This movement is the same with a tube sight with no optics. It works the same way with scopes sights with external mounts and adjustments. It goes opposite the direction you want the bullet to move. You can see this by visually bore sighting a rifle. You can really see this also in the old style bore sighter that fits into the muzzle. Turn the adjustment to the right. See which way the cross hairs move. I have had individuals become belligerent on this topic. My suggestion was to take it home and try it out. It's possible for a challenged person who will remain unnamed to get the adjustment directions mixed up in a long zero session. Doing it wrong shimming scope bases can be one of those traumatic learning experiences.

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Old June 15, 2018, 11:51 AM   #5
tpcollins
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Quote:
It's like the same as moving the front sight. This movement is the same with a tube sight with no optics. It works the same way with scopes sights with external mounts and adjustments. It goes opposite the direction you want the bullet to move.
I know that - but to hit higher the crosshair must be moved down, to hit to the right more the crosshair must be moved to the left.

To accomplish this I would think it's because the image is upside down inside the erector tube and up on the upside down image is actually going down on it. If this is NOT the case, then explain how allowing the erector tube to raise causes the POI to hit higher.
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Old June 15, 2018, 02:08 PM   #6
tpcollins
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I sent an email to a contact at Vortex and he explained exactly how it works. I'm all set.
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Old June 15, 2018, 05:05 PM   #7
Jim Watson
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Turning the knob on the scope does not move the bullet, it moves the reticle.
You are bringing the reticle to the bullet hole, so when you move the reticle down, it just LOOKS like you are moving the point of impact up. So scope adjustments are graduated as though you were changing the point of impact even though you are actually changing the point of aim.
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Old June 15, 2018, 08:02 PM   #8
Art Eatman
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RC20, the directions are those little arrows on the knobs of the turret. On my scopes, anyway.
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Old June 15, 2018, 10:37 PM   #9
std7mag
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I think i got one of Mr. Eatmans scopes...
Mine already has the arrows on it too..
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Old June 16, 2018, 05:53 AM   #10
J.G. Terry
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Don't worry about "why"

If you have a tube sight-no optics-the movement necessary to move the POI is the same. It may be different if one is standing on his head. The answer to the OP's question is "No."
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Old June 16, 2018, 01:41 PM   #11
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Keep your rifle scope crosshairs locked in on the bullseye , your shot goes high to the left. Your scope caps rar marked R ----- L and UP ----- Down. Keeping the rifle in position , move crosshairs to the bullet holes . See how your crosshairs opperate , pretty simple. Can zero in two shots or at least very close.
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Old June 17, 2018, 08:41 PM   #12
tpcollins
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You guys still miss the point. I know to chase the bullet hole - I wanted to know how the erector tube accomplishes that exactly - and now I know.
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Old June 18, 2018, 03:27 PM   #13
J.G. Terry
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Adjusting the Scope

Really, I don't think OP understands that it's not the erector that makes the adjustments. Yes, go be the arrows on the knobs. Don't worry about the rest.

The way to zero scope with the arrows is a matter of choice. For me, the most fast economical way is to have an aiming point. The scope is adjusted to bring the bullets to the aiming point. I use the small stick-on orange targets. I can't do this chasing bullet holes. YMMV For me, it's way easier to use the fixed aiming point on a zeroing in target. Shoot into the aiming point and inch marks are on the target etc. Start turning knobs. It's what ever cranks your tractor.

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