Scope Parallax

T

Target 58

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If parallax is not adequately mitigated, by setting up the scope correctly and having a consistent eye position within the scope's eye box, it seems easy enough to introduce an uncertainty factor that could make groups larger than what you and your equipment and ammo are capable of. I am wondering if I am following the gold standard and would like some feedback.

I first adjust the focus of the reticle against a diffuse background. This should be a one time action, however, sometimes the reticle is no longer crisp and I will fix that as needed. Looking at the target I then adjust parallax by focusing the target picture on the scope's highest magnification. If the target image is perfectly sharp can I assume that I have reached optimum parallax mitigation?

I wear trifocal glasses and look through the scope with the upper long-distance vision lens. I imagine that depending on your eye glass prescription the target comes into focus at a slightly different settings of the parallax knob. Which means you may not have the optimal parallax setting.

Are there any tips or tricks about the best eye position behind the scope? I know some shooters that keep their eye at such distance from the scope that they are looking down a tunnel where there is a concentric black ring around the target image in the center. Helps also with free recoil shooting of high recoil rifles. Opinions about that?
 
I do exactly as you do except for a couple of things. In close range benchrest most scopes are of fixed power usually 36-50 power. To adjust parallax I look through the scope and move my head and eye around to see if the crosshair/dot moves around on the target. If it does the parallax is not adjusted correctly. Adjust it until the crosshairs/dot does not move. This is difficult in heavy mirage. Also be aware that parallax can change during a match as the air warms or cools and you may need to adjust your settings accordingly. I do not adjust my eye focal distance to blur out the periphery of the image. I feel that you can miss mirage changes if you do this. You are correct in setting parallax at the highest power setting on your scope. The same goes for adjusting focal length.
 
Trifocal glasses, bad idea. Bifocals with line better. You will know if you move out of the top lens that produces 20/20 vision.
The parallax gets adjusted so the view is the sharpest. Forget the yardage lines.
 
If your scope has a diopter adjustment (often integrated into the ocular focus), use it to match your vision. This ensures the reticle and target image are both sharp.
 
I'll set my scopes parallax adjustment to the "infinity" setting first, then looking at
a bright cloudless sky, I focus the reticle.
 
First off, with a BR quality optic, March for instance, every session at the bench often requires small adjustment from previous. Condition changes…eye changes.
Second, for the OP, you'd likely be farther ahead buying a quality pair of shooting glasses with lenses perfect for your scope shooting makes everything a lot more comfortable.
 
A white wall or a piece of white tissue paper over the objective Lense adjust till the crosshairs are as crisp and clear as you can get them then adjust the parallax up and down first if the crosshairs move with your eye ( up they move up ) too much parallax or you are too close to infinity if they move when you move your eye up and they move down you need to increase the parallax after all that if you still have a small amount of movement left and right make a very small adjustment to the focus it should go away hope this helps
 
If everyone just read the directions that came with their scopes many would be far ahead. I often ask shooters what did the directions say, lot of blank looks. Lol.
 
Target 58 said:
If parallax is not adequately mitigated, by setting up the scope correctly and having a consistent eye position within the scope's eye box, it seems easy enough to introduce an uncertainty factor that could make groups larger than what you and your equipment and ammo are capable of. I am wondering if I am following the gold standard and would like some feedback.

I first adjust the focus of the reticle against a diffuse background. This should be a one time action, however, sometimes the reticle is no longer crisp and I will fix that as needed. Looking at the target I then adjust parallax by focusing the target picture on the scope's highest magnification. If the target image is perfectly sharp can I assume that I have reached optimum parallax mitigation?

I wear trifocal glasses and look through the scope with the upper long-distance vision lens. I imagine that depending on your eye glass prescription the target comes into focus at a slightly different settings of the parallax knob. Which means you may not have the optimal parallax setting.
Are there any tips or tricks about the best eye position behind the scope? I know some shooters that keep their eye at such distance from the scope that they are looking down a tunnel where there is a concentric black ring around the target image in the center. Helps also with free recoil shooting of high recoil rifles. Opinions about that?
Click to expand...
Vous minimisez le parallax, mais testez en bougeant la tête (réticule stable vs cible, pas juste netteté). Votre prescription affecte le réglage parallax. Visez une position d’oeil constante sans anneau noir (champ de vision complet), pas de tunnel, pour une précision optimale.
 
You minimize parallax, but test by moving your head (stable reticle vs. target, not just sharpness). Your prescription affects parallax adjustment. Aim for a consistent eye position with no black ring (full field of view), no tunneling, for optimal accuracy.

Translation of above post.
Bob
 
Remember, the weakest link in determining accuracy, will always be you. I have learned that my bench technique has been the best answer for accuracy. You have to get your eye in the exact position on the stock every time. What I do is mount the rifle, and move my head forward on the scope until the image blacks out. Then move slowly back until the image pops full.
 
JEFFPPC said:
Lol, well there is that! Besides, its my wife's job to read the direction. Real men, we forge ahead.
Click to expand...
Jeff.....Ask her if she can read Pakistani, Mandarin and Pidgeon English. and why
most of us throw the instructions out......Now about parrallax. I took 2 high dollar
tier one scopes to the range to choose the best option for an upcoming match.
Eye boxes are real close. One is on the rifle and the other I put on a stand next to it.
The higher dollar scope by about $1000 more, could dial in clear at 300 yards with 1/4
of a knob turn. The lessor valued tier one scope took 1/2 of a turn to do the same job.
Moving on to the afternoon when the sun hung higher and the Mirage going nut's,
higher dollar scope #1 had me fidgiting with the 1/4 turn parralax knob quite a bit.
The lessor valued tier one scope with it's 1/2 turn mechanics stayed clearer for longer
periods of time. Mind you that I'm running the scopes at the same time . Seems like
i was fighting the eye box more with the higher dollar tier one. With the lower valued
tier one, my eyes were more relaxed over the test period.......All tests were run at a high
of 50X on both scopes with two major changes in conditions thru out the day.

Side note.......Yes there were animals harmed in this test. Sent 3 chucks to their greener
alfalfa fields in the sky. Them Sierra 7mm 100gr varmint bullets at 3452 fps are absolute
grenades......
 
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JEFFPPC said:
Spightron SVED 10-50× 60 with its dual parallels knobs is the best I have seen at proper adjustment.
Click to expand...
Always been intriqued by that 60 mm Objective on the Sightron. I'd only wish they
would increase the power range like they did on the 56mm field scope. They went to
60x on that one. It would cut into the NF Comps large market share by a huge margin.
 
Fuj said:
Always been intriqued by that 60 mm Objective on the Sightron. I'd only wish they
would increase the power range like they did on the 56mm field scope. They went to
60x on that one. It would cut into the NF Comps large market share by a huge margin.
Click to expand...
Hey Fuj, give Sightron a call. They won't listen to me.
 
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I'll have the guy's at EuroOptics do it. I'm heading over there possibly this
week to dump my March High Master X. Going to trade it for another NF
Comp but, I may just lean towards that Sightron with the 60mm objective.
The 5x less magnification will not bother me with my eyes.
 
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