Question about the spring and erector inside a scope

T

tpcollins

New member
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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"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. :D)
 
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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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.
Click to expand...

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.
 
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.
 
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."
 
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.
 
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.:)
 
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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The only exception to the bullet strike movement is on a bunch of Red Dot sights from several "brands". The arrows are backwards. I think they're all made by the same factory, but branded differently.

When sighting-in a bunch of rifles, or if I don't trust a particular scope, I bring my Sight-Align vise to the range.

After firing a group on paper, I clamp the rifle in the Sight-Align vise and adjust the vise vertically and horizontally to put the crosshairs on the target center. Then, I make the necessary scope adjustments to bring the crosshairs to the desired relationship with the group center. That may be the target center, or hitting a desired height above target center at that range, in which case the crosshairs must be adjusted to that dimension below the group.

Removing the rifle from the vise, then firing a few shots from the bags confirms the zero.
 
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