Scope without parallax adjustment.

Buster95

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Nothing wrong with a scope with no parallax adjustment for a rifle in .223, the scope is a Vortex Diamondback Tactical 4-12x40 VMR-1. I seriously doubt I will be shooting anything beyond 300m or 400m but more than 100m. Only target, no hunting.
 
Well - The parallax was nominally set at 100 y at the factory. I say nominal, because often the actual parallax is somewhat different. Regardless, if you centre your eye properly and consistently, the parallax error is reduced or eliminated. Do your own investigation next time you are at the range.
 
Nothing wrong with a scope with no parallax adjustment for a rifle in .223, the scope is a Vortex Diamondback Tactical 4-12x40 VMR-1. I seriously doubt I will be shooting anything beyond 300m or 400m but more than 100m. Only target, no hunting.

The Parallax ajustment is MORE important for target shooting then for hunting ! I like it on any Hi powered scope ! RJ
 
I'm using a Scorpion Red-hot 17 on my CZ 17 HMR, no paralax adjustment, but like the OP, doubtful I would ever shoot beyond 250; but the scope is calibrated with the turret adjustment up to 300. It is about right on to 200, but have not checked beyond. It is fine for these ranges. Different story for my 6.5 x 55.
 
Scopes without AO (adjustable parallax) or SF (side focus) have the parallax adjusted at the factory for a set distance, usually 100 yards (sometimes 50 on scopes made as rimfire scopes).

When using a scope with parallax fixed at 100 yards, objects that are closer are more difficult to see in focus. Objects that are further are less difficult to see in focus. This is increasingly true as magnification increases. The closer the target, the more important it is to have the capability for adjusting parallax, either with AO or SF. The further the target, the less important is parallax adjustment.

With a relatively low powered hunting scope it's not hard to see objects in focus whether they are close or far away. The greater the magnification, the more necessary it is to have the ability to adjust the focus to see objects, especially those that are close.
 
Focusing an image, focusing the reticle and setting parallax are three different things - related, but different. The "test" for parallax is not image quality - set rifle on sandbags aimed at a target - move head left/right or up/down - if the reticle moves on the target without the rifle moving, you have parallax error within the scope lenses - almost always corrected by adjusting the very front lens (AO) or by similar arrangement with the Side Parrallax adjustment, apparently not to be confused with a Side Focus adjustment. On old school scope, the reticle focus is done on the rear lens. Parrallax sighting error can be reduced or eliminated by very repeatable cheek weld by the shooter - looking through the same "spot" through the lenses ever time.

On a Leupold 2-7 rimfire scope - nominally set at factory to be parallax error free at 60 yards - at about 25 yards, I can see the cross hairs move about 1" or so - by moving my eye from seeing a "half moon" blackness on one extreme, to the other extreme - left to right. That, I believe is my extreme parrallax sighting error at 25 yards with that scope - I will be "aimed" up to a half inch left or right of the actual bullet impact, at 25 yards, if I see "black" within the scope.

On "fixed" scopes without capacity for user to adjust parallax free range settings, the error will increase the further that you get from that one fixed distance's setting - both closer than that range and further from that range. So if a typical center-fire scope set to be error free at 150 yards, will be same amount of error at 15 yards as there is at 285 yards.
 
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Focusing an image, focusing the reticle and setting parallax are three different things - related, but different. The "test" for parallax is not image quality - set rifle on sandbags aimed at a target - move head left/right or up/down - if the reticle moves on the target without the rifle moving, you have parallax error within the scope lenses - almost always corrected by adjusting the very front lens (AO) or by similar arrangement with the Side Parrallax adjustment, apparently not to be confused with a Side Focus adjustment.

Indeed, it's important to note that focusing the reticle, which is achieved by the reticle focus ring on the ocular bell, is different from focusing on the image or target.

Does a parallax-free adjustment of the scope result in a sharply focused image? What's the difference between Side Focus and Side Parallax adjustment?
 
I do not own any scope with the third turret on the left - have been reading posters describing to adjust parallax to get better image of the target - not certain that is actually adjusting parallax, but might be a side-benefit of it? Have seen various scope advertisements referring to both "side parallax" and "side focus" adjustments. I know just enough to have satisfied myself, with the several scopes here, that focus of an image through lenses, is not necessarily the same thing as getting a parallax error free alignment between the reticle and that target image.

I have a Hensoldt Diatal scope here - I would describe the view as "breath taking" - just the most crisp and clear images as I have seen through a scope. But set that scope on sandbags and "aim" it at a tree trunk about 20 yards away, and moving my head left to right does definitely move that "dot" on that image. So, from that, I believe the image focus is as perfect as I have seen, but there is parallax sighting error at that 20 yard distance.

On a particular scope here with an AO front end, is showing 2 3/4" rotation as difference between 50 and 100 FEET parallax adjustment. Same scope is showing just less than 1/4" rotation as difference between 200 and 400 YARDS parallax free setting. A made-in-Japan BL stamped fixed 10 power scope.
 
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In quality SF scopes which are set up correctly at the factory, there should be no difference between correct parallax and sharp focus. Sometimes, however, scopes are not made exactly as they should be. For an explanation of why parallax is not always where the image is sharpest, see this youtube video h ttps://www.youtube.com/watch?v=VGuwbsJw0JA
 
I have never seen a scope with a "side focus" adjustment. On any scopes I have ever seen or used there is only one way to adjust the "focus" and that is with the ocular lens. There are 2 ways to adjust/correct parallax. One way is the AO and the other is the side parallax turret. Where the confusion starts is when people refer to this turret as a side focus adjustment. There is no such thing as a side focus adjustment.
 
The "side focus" thing. I think Leupold knows a bit about scopes - found this on their website - they are not helping to clarify matters!!! "VX-3 4.5-14x40mm (30mm) Side Focus"

And from the manual for that scope:

SETTING PARALLAX
1. The reticle should be clear (focused) before adjusting the parallax. If it is not, follow the instructions under “Focusing the Reticle.”
2. With the firearm in a stable position, look through the scope, concentrating on the center aiming point of the reticle.
3. Move your head slightly up and down while turning the side parallax dial or adjustable objective ring until the reticle does not move in relation to
the target.

So the name of the scope includes "Side Focus", yet that feature in the manual is referred to as "side parallax dial". What is an old guy to do with that information??
 
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The "side focus" thing. I think Leupold knows a bit about scopes - found this on their website - they are not helping to clarify matters!!! "VX-3 4.5-14x40mm (30mm) Side Focus"

And from the manual for that scope:

SETTING PARALLAX
1. The reticle should be clear (focused) before adjusting the parallax. If it is not, follow the instructions under “Focusing the Reticle.”
2. With the firearm in a stable position, look through the scope, concentrating on the center aiming point of the reticle.
3. Move your head slightly up and down while turning the side parallax dial or adjustable objective ring until the reticle does not move in relation to
the target.

So the name of the scope includes "Side Focus", yet that feature in the manual is referred to as "side parallax dial". What is an old guy to do with that information??

The instructions are dead on, no doubt. The reference to "Side focus" is misleading to say the least. That third "side turret" is either a parallax adjustment turret or a focus adjustment turret, it can not be both.Personally I have found that it is a parallax adjusment, no question. Leupold itself contributes to this confusion. The thing is, if you know how to focus your scope so you can clearly see the reticle and the target and then adjust the parallax so that the POI remains consistent with the point of aim, and you can hit what you are aiming that, isn`t that the goal no matter what you call that "third turret"
 
I am thinking, from comments I read - like wanting to install a "big game" or "center-fire" scope on a rimfire - that many shooters have never bothered with the Step 3. part - to actually check for parallax error with their scope at the target range they want to shoot. Comes from confusing an "in-focus" image, with a "parallax error free" setting.
 
Yes, I totally agree. In the past I have tried centerfire scopes on .22s and could never get consistent pin-point accuracy out of them until I learned this. A "centerfire scope" on a .22 may hit rabbits or squirrels at 20, 30 or 50 yards, but try shooting itty-bitty groups with it and see what happens. That is why rimfire scopes are made and EFR scopes were invented. Put a centerfire scope that has a parallax adjustment down to 15 or 25 yards on a .22 and see what happens. Anyone who has not tried the moving your head from side to side and up and down test should and I guarantee they will be amazed at how much the reticle moves off of the point of aim.
 
I have two Simmons 4x32 scopes on a 22 and 17 hmr - would use these on a centerfire rifle - my made up rule of thumb is 100 yards for every power so I should be good for 400 yard shots using a centerfire rifle.
 
For all practical purposes, Side Focus and Side Parallax Adjustment are interchangeable terms. Leupold and Sightron, for example, refer to the adjusting knob opposite the elevation turret as "Side Focus", while Nightforce, for example, calls it Side Parallax Adjustment. Both do the same thing. One will give a minimum distance at which focus is achievable, the other a minimum distance at which parallax is adjusted. In both cases parallax is correct and focus is sharp.
 
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