Rifle Scopes  Parallax Adjustment.

RotARy15

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Help inform this newbie on parallax adjustment. Specifically, why do a lot of optics skip certain ranges in adjustment?

I have noticed optics that list parallax settings in an order such as, 75-100-150-200-300-500-600-700-infinity.

It skips the 400 yard setting and the progression has no uniformity. Is there a reason for this? I understand basic parallax but am not an expert. Am I missing something?

Thanks in advance,
 

oldfatguy

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Re: Parallax Adjustment.

Parallax adjustment is typically done while looking thru the scope at the target. Turn the adjustment knob to infinity and slowly turn it back until the target is in sharp focus.

This works for most people. However it is possible to have the sharpest image and still not have removed all the parallax. In that case move your eye side to side or up and down while turning the knob. When there is no apparent reticle shift on the target when you move your eye then all the parallax is adjusted out.

Some high end scopes do not even have numbers on the adjustment at all.

OFG
 

TOP PREDATOR

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Re: Parallax Adjustment.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RotARy15</div><div class="ubbcode-body">Help inform this newbie on parallax adjustment. Specifically, why do a lot of optics skip certain ranges in adjustment?

I have noticed optics that list parallax settings in an order such as, 75-100-150-200-300-500-600-700-infinity.

It skips the 400 yard setting and the progression has no uniformity. Is there a reason for this? I understand basic parallax but am not an expert. Am I missing something?

Thanks in advance,</div></div>

1. they can't fit (label) all the numbers in the small space

2. they figure if you can split the difference between 300 and 500, you must be around 400.

3. it's not set in stone, for your eye (and especially on cheaper scopes) you may find it's clearest B-4 or after the labeled distance you intend on shooting at. also on the cheaper scopes, you may see it will vary with the power of magnification you are on.

4. you'll also find the lesser distances more commonly labeled as that's the range where most of the shooting public will be shooting.

5. as you go up in labeled distance, you'll see the space between the labeled distances gets less as a smaller adjustment makes more of a difference, just like adjusting an elevation or windage turret.

many of the reasons why you shouldn't use the parallax adjustment as a ranging tool, as some say is OK to do. a very rough yardage, maybe, but not something that should be relied on for ranging.
 

RotARy15

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Re: Parallax Adjustment.

Do the parallax knobs have clicks that the knob snaps to or are they smooth like a magnification knob that can be set between numbers?

I've messed with many scopes but never really noticed whether the parallax is clicked or not.
 

RotARy15

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Re: Parallax Adjustment.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TOP PREDATOR</div><div class="ubbcode-body">

1. they can't fit (label) all the numbers in the small space

2. they figure if you can split the difference between 300 and 500, you must be around 400.

3. it's not set in stone, for your eye (and especially on cheaper scopes) you may find it's clearest B-4 or after the labeled distance you intend on shooting at. also on the cheaper scopes, you may see it will vary with the power of magnification you are on.

4. you'll also find the lesser distances more commonly labeled as that's the range where most of the shooting public will be shooting.

5. as you go up in labeled distance, you'll see the space between the labeled distances gets less as a smaller adjustment makes more of a difference, just like adjusting an elevation or windage turret.

many of the reasons why you shouldn't use the parallax adjustment as a ranging tool, as some say is OK to do. a very rough yardage, maybe, but not something that should be relied on for ranging. </div></div>

Cool. Thanks. I've always been turning to the number and just assuming the parallax was set. I guess I took for granted and never bothered to check for parallax when I could just turn to the number and send it.