150yd Fixed - Parallax Scope!?

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SwP

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In terms of accuracy and shooting predators all the way out to 400yds - taking into consideration a Ruger American Predator chambered in .223, firing 53gr Hornady Superformance.
Is it recommended that one zeros at that (150yd) distance to begin with, for gauging maximum accuracy? Or utilizing the 1/4 MOA @ 100yd adjustment parameters?

*surely parallax error also taken into consideration and that the scope is the "1/4 MOA @ 100yd" adjustment turret/s
 
Hard to say what your variance will be because after you broach the parallax setting your eye position behind the scope comes into play.

The best way to answer your question is this: Most fixed parallax scopes will have roughly a 1" error for every 100 yards before and past the parallax setting. If you are shooting for accuracy from a bench and measuring your groups, this could get frustrating quickly. But in a hunting situation a 1" variance is hardly a problem (unless we're shooting prairie dogs at extreme distances). To get the most out of your scope, or any fixed parallax scope, it is best to zero at the parallax distance and adjust your POI from there at distances you shoot.

I'm not a "turret cranker" and prefer to use a dope sheet if holdovers are necessary. And in a predator hunting situation I've never had the time to turn a turret anyway. In other words ... use a ballistics calculator (several online) and set the zero distance at 150 yards. Then you will see the adjustments you will need to make at other distances.

Parallax error on fixed parallax scopes will always be there unless the shooter can get behind the scope in EXACTLY the same position EVERY time. And I've never known anyone who could do that ... especially in a hunting situation.

HTH.
 
Equation max PE = .5(D) ABS(t-p)/p
PE - parallax error
D = objective lens dia
ABS absolute value
t-p = target distance - parallax distance
So your 40 mms scope/150 yard parallax setting
@400 .5x40x250/150= 33.3mm or 1.311 inches
@200 .5x40x50/150= 6.6mm or .259 inches
@50 yards .5x40x100/150= 13.3mm or .523 inches.
 
Emphasis on maximum Paralax Error. Meaning your eye is maximum misaligned to one side for the shot. That's the maximum error. But assuming your eye is only slightly or moderately misaligned from shot to shot, parallax error is much less than the maximum value. Say 25% error, or maybe 50% in a hasty hunting scenario. Is that enough to worry about at reasonable (predator) hunting distances? No!
 
I never knew how much a scope could be off with a fixed parallax scope. Both DD and SSS helped clear that up
 
In terms of accuracy and shooting predators all the way out to 400yds - taking into consideration a Ruger American Predator chambered in .223, firing 53gr Hornady Superformance.
Is it recommended that one zeros at that (150yd) distance to begin with, for gauging maximum accuracy? Or utilizing the 1/4 MOA @ 100yd adjustment parameters?
*surely parallax error also taken into consideration and that the scope is the "1/4 MOA @ 100yd" adjustment turret/s
When sighting in off the bench, move your head back to where you are only seeing half of the image through the scope.

That will eliminate most, if not all of, the potential parallax issues.

I sight in all of my guns for a 200 zero, with zero regards to the scope's parallax setting.

Proper scope mounting for eye relief & height should be where you can close your eyes, bring your gun to bear, open your eyes, and you should be looking through the middle of the scope w/o needing to move you head to do so.

Shooting out to 400 is really a non event in worrying about fixed parallax in a hunting environment.

I've shot a five shot 12" group at 1400 yards with a 10X & fixed parallax, you just need to be looking through the middle.
 
Proper scope mounting for eye relief & height should be where you can close your eyes, bring your gun to bear, open your eyes, and you should be looking through the middle of the scope w/o needing to move you head to do so.

Shooting out to 400 is really a non event in worrying about fixed parallax in a hunting environment.

All correct. (y) Unless you're concerned about minute-of-mouse at 400 yards, hitting a coyote shouldn't be an issue.
 
I seriously doubt with a factory rifle and Hornady superformance ammo is capable of shooting well enough to "see" parallax error on 400 yard targets, with the stated 150 yard focus setting. Wind drift, even a light breeze fluctuating 0-5 @ 3 or 9 would be almost 8"@ 400 yards.
 
I appreciate all the answers, definitely educated myself in such a short time with this post! Thanks to you all! Hunt on!
 
Hard to say what your variance will be because after you broach the parallax setting your eye position behind the scope comes into play.

The best way to answer your question is this: Most fixed parallax scopes will have roughly a 1" error for every 100 yards before and past the parallax setting. If you are shooting for accuracy from a bench and measuring your groups, this could get frustrating quickly. But in a hunting situation a 1" variance is hardly a problem (unless we're shooting prairie dogs at extreme distances). To get the most out of your scope, or any fixed parallax scope, it is best to zero at the parallax distance and adjust your POI from there at distances you shoot.

I'm not a "turret cranker" and prefer to use a dope sheet if holdovers are necessary. And in a predator hunting situation I've never had the time to turn a turret anyway. In other words ... use a ballistics calculator (several online) and set the zero distance at 150 yards. Then you will see the adjustments you will need to make at other distances.

Parallax error on fixed parallax scopes will always be there unless the shooter can get behind the scope in EXACTLY the same position EVERY time. And I've never known anyone who could do that ... especially in a hunting situation.

HTH.
Gotcha!! Thanks for taking the time to answer!
 


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