Try as you want, you cannot group your shots. The scope is zeroed, you checked the mounting, cant, and everything you can think of. Yet, one thing is still to consider – parallax. Would having a rifle scope with parallax adjustment solve the issue and you’d be able to group your shots?
There are many talented shooters who just cannot nail a sub-MOA group over a distance. The fault may not necessarily be due to their skill but due to misunderstanding their rifle scope’s side focus parallax adjustment and what it is for. It is a crucial aiming aid for making the shot with an error of less than a few inches over a 300-yard target.
The majority of scopes with a magnification of 8x or higher come with the parallax adjustment. One important thing to note here is that the yardage markings on the parallax adjustment dials are not always accurate.
To get the precise adjustment of the parallax on a scope, you will need to test it out through trial and error until you get it right for different shooting ranges.
In the following, we will take a detailed look at what parallax in rifle scopes is and the adjustment that will help you get the correct parallax for your rifle scope.
What is Parallax on a Scope?
The rifle scope parallax is a kind of optical illusion. It makes the target look out of focus when you move your head or eye slightly right or left from the center of the eyepiece when you’re looking through the scope. It makes the focal plane of the target’s position appear offset from the reticle center.
Scope parallax generally occurs at a high level of magnification and can lead to a lot of missed shots. If it happens for you while aiming, it means one of two things. Either the target image and retina center are not on the same focal plane or the scope is out of focus when you’re looking through the scope.
The objective lens projects and focuses the image at a specific distance in the scope. Changes to magnification settings that you’ll perform for long-range targeting as well as moving your head can impact that distance so you don’t get a clear and crisp sight picture and face parallax issues.
When you adjust the side focus parallax, the distance of the projection of the sight picture of the objective lens is moved until you end up with a clear target image again.
Parallax generally isn’t a concern when you are shooting at a distance of 250 yards or less. Riflescopes with fixed parallax have their focus set at 150 to 200 yards which is fine for shooting at a shorter distance, or a distance of up to 250 yards.
Parallax in scopes can become a problem at distances over 250 yards, where you need to massively magnify the sight picture. However, if you have your scope dialed in high power and you suddenly have a target at a short distance, then parallax can also become a factor.
Why Do You Need to Adjust Parallax?
An adjustment to the parallax is needed because it helps to get rid of the optical illusion while aiming. It causes the crosshairs of your reticle to appear fixed on the target regardless of how you move your eye.
Adjustable parallax in scopes is a good thing because it makes aiming easier and also improves your shooting accuracy. A lot of rifle brands and scope manufacturing companies have added this innovative feature in their products to adjust parallax for the gunner so that shooting accuracy is improved. For example, Nikon Black, Leupold VX3, or Bushnell Elite 4200 rifle scopes all come with the parallax adjustment feature.
The adjustment for side focus parallax is carried out by moving the reticle’s plane to the same distance as the plane’s image. The effect is mostly achieved in small increments when you adjust the parallax.
The point of impact for the bullet shifts every time an adjustment is made on the scope, so you should plainly mark which direction to turn on the turret for the necessary correction on the reticle.
That means you will need to adjust the parallax setting every time you change the shooting range and adjust your scope.
Parallax at Long Distance
If you are shooting long distances with any magnification over 7x, then side focus parallax adjustment will be an important factor. Once you have set the scope’s zoom to the desired level, you can correct the error by adjusting the side focus parallax compensation turret or objective lens ring while looking through the scope.
This will help align the focal planes of the scope and reticle. Move your head and eye around when you’re looking through the scope to check if there is any movement of the reticle when you shift your gaze.
Keep making adjustments to it until the reticle is perfectly in place and the reticle is fixed for the zoom level. Use a fine permanent marker to mark the point on your ring or turret for this range.
Parallax at Varying Distances
You will need to adjust the parallax when you are shooting at varying distances, just like the scope. While it may sound cumbersome and slow to adjust your scope’s parallax setting for every range, it’s something that you only have to do once when you start shooting at that distance. As mentioned before, it’s usually an issue for long-range shooting.
If you want to make things easier, you can keep notes on paper (or in your head) during practice. Once you know that your rifle scope’s parallax dial should be at the 80-yard mark for a target at 100 yards, 250-yard mark for a 250-yard target, and 400-yard mark for a 350-yard target, you won’t have to do the testing again and again.
What Does Parallax Corrected Mean?
Once you have set up your parallax adjustment properly, the reticle will look like it has been locked in place and always focused solely on the target. No matter which way you shift your gaze, the position of the target will not change on the crosshair.
Parallax is barely noticeable at a close range and you will not have to adjust it when shooting at less than 100 yards.
What is a Parallax Free Scope?
In parallax-free scopes, the parallax is set up internally and locked in place for all ranges of magnification. These scopes are generally designed for close-range shots and operate nicely for a range of 100 yards to 400 yards. Such a rifle scope is not truly parallax-free but instead comes with a fixed parallax.
If you’re carefully looking through the scope’s ocular and objective lens and move your head and eye around, you will detect a very slight parallax error for these scopes, even at a short-range. But this parallax error isn’t very noticeable when you’re looking through the scope.
These scopes are ok when you are hunting, but if you are shooting for a sports competition, then you will need to get a scope with parallax error adjustment.
Does A Reticle On First Or Second Focal Plane Require Different Parallax Adjustments?
The first and second focal plane scopes identify where the reticle is placed inside the scope. The reticle is placed just in front of the magnification lens in a first focal plane (FFP) scope.
This positioning will make the reticle grow and shrink in size when you adjust the scope range. On a fixed magnification scope, the reticle will always look the same size as there is no magnification.
For a second focal plane (SFP) scope or rear focal plane (RFP) scope, the reticle is placed just behind the magnification lens. The size of the reticle will not change as you adjust magnification power. The reticle looks the same at every power setting.
The parallax adjustment for both FFP and SFP would be similar. However, as the size of the reticle also enlarges for FFP scopes at a greater distance, you will need to adjust it with greater precision.
Does the Focal Point Impact the Parallax At All?
Yes. It has a massive effect on parallax. You will see the reticle move in every direction from the target when you move your head or your eye.
The reason is that the focal point for your scope may not always be the same as the focal point for the target. Rifle scopes are always designed to be used at specific distances. Even the ones with an adjustable zoom have a range. The parallax is adjustable for rifles with a big zooming range.
When you are shooting at a target that is hundreds of yards away then you need to be able to adjust the focal points of the lens and reticle. This will help you line up the focal planes to where they are designed to be.
If the focal planes don’t line up, you will only be able to focus on the target or the crosshair but not both, and parallax will become a major problem.
Are All Red Dot Sights Parallax Free?
Parallax-free red dot sights have become quite popular for shooting. They allow gunners to get the best use of the sighting aid even under intense conditions. The underlying concept for these scopes is simple. Once you go past a certain range, the gun will remain on target regardless of where you see the dot on the optic.
Almost every popular red dot sight in the market is parallax-free. While no optic sight can ever claim to be truly parallax-free and lose all optical distortion, it can be designed to be nearly parallax-free at certain ranges.
This will always be specified with the red dot sight you buy. Make sure you get the sight that meets your needs. If you are going to use the rifle for deer hunting, a red dot scope of 150 – 250 yards should do the trick.
You will want to get the red dot because it will make your shooting easier. Perhaps not technically correct, but it makes hunting a breeze. Just sight the dot on the reticle and pull the trigger. If the dot is on the target you will hit the target, even if you are moving and don’t get time to aim for perfection.
We hope you learned something reading this post. If you have any questions or want to share your experiences then please leave a comment below.
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