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Old August 23, 2019, 05:08 PM   #1
Bart B.
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What moves up?

When you twist your scope's elevation knob in the direction arrowed "UP," what moves up on target when you regain the sight picture?

* Line of fire; point of bullet impact.

* Line of sight; point of aim.

I ask 'cause I think March scopes' instructions in their manuals are wrong.

Last edited by Bart B.; August 26, 2019 at 07:40 PM. Reason: Better clarity
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Old August 23, 2019, 05:14 PM   #2
MTT TL
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Quote:
When you twist your scope's elevation knob in the direction arrowed "UP," what moves up on target?
Nothing, The target does not move.
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Old August 23, 2019, 05:40 PM   #3
zukiphile
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Quote:
Originally Posted by Bart B.
When you twist your scope's elevation knob in the direction arrowed "UP," what moves up on target?
My approach isn't very sophisticated. I never look at the directions on the knob. I assume that if I turn a knob clockwise the reticle will move in the direction of the knob and the point of impact will appear to move in the opposite direction relative to the reticle.

If I'm wrong, that gets obvious pretty quickly.
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Old August 23, 2019, 05:47 PM   #4
Bart B.
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Quote:
Originally Posted by zukiphile View Post
I assume that if I turn a knob clockwise the reticle will move in the direction of the knob and the point of impact will appear to move in the opposite direction relative to the reticle.

If I'm wrong, that gets obvious pretty quickly.
Are you thinking if the elevation knob is turned clockwise and moves down, the reticle will move down on the target and bullet impact will be further above point of aim?
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Old August 23, 2019, 05:57 PM   #5
zukiphile
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Quote:
Are you thinking if the elevation knob is turned clockwise and moves down, the reticle will move down on the target and bullet impact will be further above point of aim?
In my model, turning the elevation knob clockwise will raise the reticle relative to the point of impact. I imagine a stationary screw that pulls the reticle up when turned clockwise, and pushes it down when turned counter-clockwise.

On most of my scopes, that works.
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Old August 23, 2019, 07:17 PM   #6
Bart B.
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Originally Posted by zukiphile View Post
In my model, turning the elevation knob clockwise will raise the reticle relative to the point of impact. I imagine a stationary screw that pulls the reticle up when turned clockwise, and pushes it down when turned counter-clockwise.
Twist the knob one full turn watching it move to see which way it goes.

Twist back one full turn; again, watching.
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Old August 23, 2019, 07:48 PM   #7
cw308
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Looking through the scope your bullet hits low , if you look through the scope while moving your dial UP you will see your horizontal hair lower to the bullet hole
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Old August 23, 2019, 09:11 PM   #8
zukiphile
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Quote:
Twist the knob one full turn watching it move to see which way it goes.

Twist back one full turn; again, watching.
That's how I confirm it.

I have a prismatic I like a lot, but it works the other way. Even though I know it works contrary to the dominant pattern, I adjust in the wrong direction about half the time.
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Old August 23, 2019, 09:38 PM   #9
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The bullet impacts move in the direction desired.

So you take aim at a fixed point. (Center Of target for example). Fire 3-5 rounds. See where they fall in relation to where you are aiming.

Then changed the scope the correct number of clicks you want the group to go. If the group fell up and right of the target you want to move it down and left for example.

Fire a new group at the same fixed target. Adjust again as necessary until your group is landing where you want it under your reticle.
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Old August 24, 2019, 08:26 AM   #10
Bart B.
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Zukiphile, what make and model is your prism sight?
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Old August 24, 2019, 09:40 AM   #11
zukiphile
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Bart, the one to which I am referring was marketed by Monstrum, an outfit that can fairly be associated with "airsoft". It's a 2x with a sort of VCOG reticle. It sits on a 22lr Lothar Walther and has "Monstrum" in big white letters on one side. https://monstrumtactical.com/s232p-2...roduct-reviews They might as well have Printed "Cheap" instead. It's clear and makes nice groups on the LW.

But...

The reticle moves in a direction opposite the way I described above. In practice this simple reversal is confounding.

For what I paid, I can live with that, but it's not the same end of the market as your March.

Last edited by zukiphile; August 24, 2019 at 10:38 AM.
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Old August 24, 2019, 12:17 PM   #12
reynolds357
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Line of sight.
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Old August 25, 2019, 07:49 AM   #13
Bart B.
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When you twist your rear aperture sight's elevation knob in the direction arrowed "UP," what moves up on target?

* Line of fire; point of bullet impact.

* Line of sight; point of aim.
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Old August 25, 2019, 09:13 AM   #14
reynolds357
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Line of sight. Point of aim. It's a no brainier.
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Old August 25, 2019, 09:56 AM   #15
Don Fischer
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Not so sure I understand the question. If it's what I'm thinking, the thing that moves is the strike of the bullet. If it's what way do the crosswire's move, not a clue, never worried about it so long as the strike of the bullet moved.
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Old August 25, 2019, 10:22 AM   #16
zukiphile
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Quote:
Originally Posted by Bart B.
When you twist your rear aperture sight's elevation knob in the direction arrowed "UP," what moves up on target?

* Line of fire; point of bullet impact.

* Line of sight; point of aim.
Quote:
Originally Posted by reynolds357
Line of sight. Point of aim. It's a no brainier.
It's actually the opposite on an A2 rear aperture. The "up" arrow points clockwise. Turning that wheel clockwise raises the rear aperture. As it rises, the point of impact gets higher relative to the point of aim.

Last edited by zukiphile; August 25, 2019 at 10:59 AM.
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Old August 25, 2019, 11:32 AM   #17
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If you change your settings without moving the firearm -

Moving the rear sight or aperture "up", the front & rear sight alignment will move down on the target, prompting you to elevate the muzzle which moves the bullet impact up.

Rotating the scope elevation knob "up" will move the reticle down on the target, prompting you to elevate the muzzle to move the bullet impact up.

In both cases, changing the elevation in the "up" direction moves the sighting element (line of sight) down on the target.
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Last edited by LeverGunFan; August 25, 2019 at 04:16 PM.
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Old August 25, 2019, 02:07 PM   #18
reynolds357
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Quote:
. It's actually the opposite on an A2 rear aperture. The "up" arrow points clockwise. Turning that wheel clockwise raises the rear aperture. As it rises, the point of impact gets higher relative to the point of aim.
You are missing it. If you move a sight, front or back, up or down; What changes? Rifle is on a linear bearing sled, you move sight. What changed? Point of impact didn't change, the rifle is locked down. POI does not change until you move the rifle.
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Old August 25, 2019, 02:11 PM   #19
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By looking through your scope and moving your crosshairs to the point of impact without moving the rifle position is the procedure . They can word it anyway they want , I'm sure everyone can figure out how to adjust . Even with a type of. Now setting up the scope , mount and rings is another animal and harder to do correctly even with good instructions .
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Old August 25, 2019, 03:38 PM   #20
zukiphile
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Quote:
Originally Posted by Reynolds357
Line of sight. Point of aim. It's a no brainier.
Quote:
Originally Posted by Reynolds357
Quote:
It's actually the opposite on an A2 rear aperture. The "up" arrow points clockwise. Turning that wheel clockwise raises the rear aperture. As it rises, the point of impact gets higher relative to the point of aim.
You are missing it. If you move a sight, front or back, up or down; What changes? Rifle is on a linear bearing sled, you move sight. What changed? Point of impact didn't change, the rifle is locked down. POI does not change until you move the rifle.
Note the underlined language.

Bart's question isn't whether an immobilized rifle moves when the sights are adjusted. Rather the inquiry is the direction in which they change in response to adjustment. It isn't a trick question.

Complicating the answer is that some manufacturer's seemingly mean different things by "up" and "left", or don't seem to have right hand threads in the adjustment mechanisms.
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Old August 25, 2019, 05:57 PM   #21
Bart B.
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I may have to edit my query.

Thanks to all respondents' comments. Didn't think of all the complications.
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Old August 25, 2019, 07:34 PM   #22
zukiphile
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Bart, for what it's worth, I just checked an old Bushnell that has caps marked the same way March marks its caps.

The direction on these caps are for point of impact. The windage cap indicates clockwise is "left". I turn it clockwise and the reticle moves right, which would put the point of impact to the left.

This is part of why I stopped looking at lense cap instructions. I think your conclusion that the March instructions have it reversed is correct.
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