Help me figure out scope parallax....

[Koda]

On my higher quality scope with a parallax adjuster I can seem to dial parallax away pretty good at 50yds and beyond, but closer shots I still get some parallax variation, is this normal or can it be adjusted?

My higher quality variable scope without parallax I cant do anything, it seems to become minimal around 50 and out. Its a quality optic but is there a way to adjust this type?

On my low quality variable scope with a parallax adjuster I can seem to dial parallax out pretty good at any distance. But this scopes parallax knob goes all the way down to 5yds

On my low quality variable scope without parallax, it just sucks at all distances.

Whats the best way to adjust parallax?

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[K-22]

On my higher quality scope with a parallax adjuster I can seem to dial parallax away pretty good at 50yds and beyond, but closer shots I still get some parallax variation, is this normal or can it be adjusted?

My higher quality variable scope without parallax I cant do anything, it seems to become minimal around 50 and out. Its a quality optic but is there a way to adjust this type?

On my low quality variable scope with a parallax adjuster I can seem to dial parallax out pretty good at any distance. But this scopes parallax knob goes all the way down to 5yds

On my low quality variable scope without parallax, it just sucks at all distances.

Whats the best way to adjust parallax?

What higher quality scope are you referring to?
Best,
Gary

 

[Koda]

What higher quality scope are you referring to?
Best,
Gary

My two best scopes are Leupolds.

 

[K-22]

My two best scopes are Leupolds.

Model, power, etc, ?
Best,
Gary

 

[Koda]

Model, power, etc, ?
Best,
Gary

Forgive me I probably should have put more details in the OP my thinking at that moment was this was more of a generic scope question but I can see how brand and type maybe can affect this.

My best Leupold is a VX-6HD 3x18x50mm on a bolt action big game hunting rifle. I notice a fair amount of reticle movement under 50 yds which is the minium the parallax dial goes to. Not my biggest concern with this setup.
Second best is Leupold VXR 3x9x40mm with no parallax adjustment on a 3030 lever gun.
The low end scopes are both UTG 3x9x40 Hunter model mounted on an air rifle. This one has a parallax adjuster that goes way down to 5 yds and seems to have no reticle movement once dialed to the target distance. The other UTG scope is a 1x8x28 Accushot tactical model on an AR15. The Accushot has no parallax adjustment and seems to be the worst for reticle movement, I havent spent much time with it but think its affecting its groupings between different cheek welds when firing. Not certain if its that or I havent found a good load the rifle likes.

 

[DLS]

To adjust parallax on a scope without external adjustment you need to use a strap wrench and remove the ocular ring. You can then use a spanner to turn the lens mounting in or out adjusting the parallax. This is how it's done during manufacture.)

It's totally not worth the effort for two major reasons:

1. The amount of bullet impact displacement due to parallax is very overstated, and at typical ranges and with typical scopes amounts to less that a bullet diameter in displacement. Even when it's more, most shooter / rifle / load combinations (in the real world) are not accurate enough to ever notice.

2. You can loose the internal nitrogen charge if done wrong.

I've done it on two variable rifle scopes to bring the parallax back from the common 100 yard setting to 50 yards because these scopes were being dedicated to .22LR match guns. While it made me feel better my scores didn't move one bit due to this tinkering. I doubt I would ever mess with it again, and if parallax was really that important to my shooting I would simply buy a scope (or have the manufacture set a scope in the factory) at the desired distance.

 

[DLS]

.... I notice a fair amount of reticle movement under 50 yds which is the minimum the parallax dial goes to....

Solidly brace the rifle in a shooting rest. Move your eye to the extreme limit (right or left / up or down it doesn't matter) that still allows you to see the reticle in the eyepiece. Using the rests adjustments, center the reticle on an aiming mark and touch off a round.

Now move your eye to the opposite extreme and once again aim at the mark using the rest's adjustment controls. Touch off another well triggered shot.

Now look at the difference between bullet impact. That is the maximum bullet displacement if (and it's a huge if) you were to actually shoot with your eye drastically misaligned with the scope. You will be surprised by how small it is, especially considering how much bally hoo scope manufactures whip up over this price increasing feature.

When shooting for real, with your cheek on the comb of the rifle, rarely will you have even 1/10 this much misalignment. You will have a correspondently smaller displacement of the shot as well.

 

[Koda]

To adjust parallax on a scope without external adjustment you need to use a strap wrench and remove the ocular ring. You can then use a spanner to turn the lens mounting in or out adjusting the parallax. This is how it's done during manufacture.)

It's totally not worth the effort for two major reasons:

1. The amount of bullet impact displacement due to parallax is very overstated, and at typical ranges and with typical scopes amounts to less that a bullet diameter in displacement. Even when it's more, most shooter / rifle / load combinations (in the real world) are not accurate enough to ever notice.

2. You can loose the internal nitrogen charge if done wrong.

I've done it on two variable rifle scopes to bring the parallax back from the common 100 yard setting to 50 yards because these scopes were being dedicated to .22LR match guns. While it made me feel better my scores didn't move one bit due to this tinkering. I doubt I would ever mess with it again, and if parallax was really that important to my shooting I would simply buy a scope (or have the manufacture set a scope in the factory) at the desired distance.

very useful info... yeah I wont be modifying my scopes. Its good to confirm my guess was the factory sets parallax at a common 100yds, especially for those 3x9 range models. Im getting good groups with my Leupold 3x9 so I'll call that one done. The cheap UTG 1x8... is it probable a cheap scopes parallax could still be an issue? Everything else on the UTG scopes are actually pretty decent for the money.

 

[Koda]

Solidly brace the rifle in a shooting rest. Move your eye to the extreme limit (right or left / up or down it doesn't matter) that still allows you to see the reticle in the eyepiece. Using the rests adjustments, center the reticle on an aiming mark and touch off a round.

Now move your eye to the opposite extreme and once again aim at the mark using the rest's adjustment controls. Touch off another well triggered shot.

Now look at the difference between bullet impact. That is the maximum bullet displacement if (and it's a huge if) you were to actually shoot with your eye drastically misaligned with the scope. You will be surprised by how small it is, especially considering how much bally hoo scope manufactures whip up over this price increasing feature.

When shooting for real, with your cheek on the comb of the rifle, rarely will you have even 1/10 this much misalignment. You will have a correspondently smaller displacement of the shot as well.

I'll give that a try next range session. Im not too concerned with close in shots (under 50yds) with the bolt rifle since its set up for 1-300yd shots currently so I think this scope will work out fine.

 

[Koda]

Im actually surprised to read shot displacement is overstated. When I test for it by moving my eye alignment often the crosshair center moves quite a bit around an aiming mark when eye alignment is at its extremes, much greater than my best rifles grouping precision. its good to know its overstated but it piques my curiosity how it doesn't affect shot placement as great as is appears in the scope...

 

[DLS]

When you move your eye you see the reticle move. But before you shoot you aim the reticle at the aiming mark removing much of the deviation. Give the exercise a try next trip to the range. It's rather revealing.

There was a pretty detailed thread on this about 5 years ago or so on Rimfire Central. I posted a pretty detailed (and long-winded) explanation of the mechanics of it all and it seemed to be appreciated. I'll see if I can dig up that "treatise" and post it here if anybody is interested.

 

[Koda]

@DLS if its an easy search for you I wouldnt mind reading up on it. I watched a couple youtube vids yesterday on this and learned its caused when the reticle isnt focused on the same plane as the target. This explains why longer range scopes tend to have the dial, but its still a rather confusing subject for me to understand how it might affect my precision. Im relieved to learn its an overstated "problem", which explains why its never been an issue for me in the past especially with the nicer scopes like Leupold.

What brought it to my attention was when I recently put a cheap UTG on an AR and wasn't happy with the grouping so Im still not certain if parallax is an issue with cheap production scopes. Id rather replace the scope then chase my tail on that one (otherwise its a decent scope). It has the worst noticeable parallax when tested by moving my eye from the scope axis.

 

[Member 5605]

Parallax...

Non adjustable scopes are often set at 100-150y, some even as close as 75y

fixed optics you cannot adjust. They are set. When the focal distance of the optic does not match the distance you are shooting, the distance and reticle are out of alignment thus being able to move the crosshairs on the target. Moving crosshairs can mean bad shot placement. Always pick/match the optic to your rifle.

I have rimfire rifles with a built in parallax of 60-75y. It's understood and I know the setting. I know my sweet spot is 40-100. I know with 200y shots I can miss if I'm not centered on the reticle.

This is a really interesting tidbit and problem to have. There aren't ways to adjust unless you have the side focus.

I like to geek on these things. It's fun.

This explains why longer range scopes tend to have the dial, but its still a rather confusing subject for me to understand how it might affect my precision.

Think of a focal plane (vertical wall in front of you), when your target distance and this wall don't align that's where your eye will shift the crosshairs/reticle. Your eye focuses at 150(scope focal), target is 75. Your eye can make the target in focus even if the scope isn't focused at that distance. This error makes the reticle move.

Maybe that helped, maybe it didn't.

 

[Koda]

Parallax...

Non adjustable scopes are often set at 100-150y, some even as close as 75y

fixed optics you cannot adjust. They are set. When the focal distance of the optic does not match the distance you are shooting, the distance and reticle are out of alignment thus being able to move the crosshairs on the target. Moving crosshairs can mean bad shot placement. Always pick/match the optic to your rifle.

I have rimfire rifles with a built in parallax of 60-75y. It's understood and I know the setting. I know my sweet spot is 40-100. I know with 200y shots I can miss if I'm not centered on the reticle.

This is a really interesting tidbit and problem to have. There aren't ways to adjust unless you have the side focus.

I like to geek on these things. It's fun.




Think of a focal plane (vertical wall in front of you), when your target distance and this wall don't align that's where your eye will shift the crosshairs/reticle. Your eye focuses at 150(scope focal), target is 75. Your eye can make the target in focus even if the scope isn't focused at that distance. This error makes the reticle move.

Maybe that helped, maybe it didn't.

this is helpful. so basically with fixed parallax optics you have to learn proper cheek weld and or eye alignment and just put up with the crosshairs being out of focus at the close in distances?

 

[Member 5605]

this is helpful. so basically with fixed parallax optics you have to learn proper cheek weld and or eye alignment and just put up with the crosshairs being out of focus at the close in distances?

Yes, otherwise your POA and POI will shift. If it isn't the same every time, shooter error will appear.