bgbuck153
Well-Known Member
This is a discuss that I can't seem to find the answer for ? Can you put it on infinity and it will be clear at all ranges or does it come into play past your last yardage mark ?
What does infinity mean on my side focus knob ?
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bgbuck153
Well-Known Member
So I comes into play 153yards past the last yardage mark ?
deadidarren
Well-Known Member
153 short for bgbuck153 lightbulb
kcebcj
Well-Known Member
Just disregard all the yardage marks etc. on the knob. They are basically just for reference. What I do is spin the knob till the image I'm looking at becomes focused then adjust up or down till the parallax is gone. I don't care what yardage number it's sitting on or if it focused perfectly if I'm parallax free.
7magcreedmoor
Well-Known Member
The infinity marking on your "Parallax Adjustment" knob denotes where it really isn't possible to have a meaningful range number anymore because the range numbers will be changing faster and faster for less knob movement. You may have noticed that the numbers at the short range end of the scale are farther apart, and how they get closer together on the knob as you go farther out. It is sort of like they way each hundred yard increase in distance takes more clicks on the elevation turret than the preceding hundred did, but backwards. There are numerous articles on parallax that you can search, but here's the short version:
Parallax in a rifle scope is the optical effect produced by the difference in location inside the scope of the image of your target and the image of the reticle. Your Parallax knob allows you to bring these two different images into the same plane, so that any movement of your head out of exact alignment with the optic will not move your point of impact on the target. Many knobs are marked with ranges on them, but most are not precise, just a general guide. The method to adjust your scope to eliminate parallax is to get the rifle solidly supported and trained on target, then run the knob past infinity till it stops, then slowly bring it back while moving your head slightly without moving the rifle. When the reticle no longer appears to float around in relation to target, you are parallax free. This is the best condition to shoot from. Any parallax present makes your aim subject to optical error. For close range shots on big game, some parallax isn't likely to be a deal breaker, but the farther out you go, the more critical it will be, turning a half MOA rifle into a 3MOA shooter at the ultimate moment. Some scopes are calibrated better than others as far as the markings on the knob, but seldom are they spot-on. A few have a moveable knob cover (like your turret knob for zeroing elevation) that lets you set your scope parallax free at a specific range, say 500 yards, then slip the knob to match the 500 yard mark. Still no guarantee the other settings will line up perfectly. I generally set the knob to whatever distance I am using as my base Zero to carry the rifle or make snap shots while stalking. When setting up for a longer shot, where I have had time to lase and dope the wind, one of the steps in the process is always to adjust parallax as described earlier. And the marking on the knob is never exactly what the laser said the range was. Hope this helped some.
Parallax in a rifle scope is the optical effect produced by the difference in location inside the scope of the image of your target and the image of the reticle. Your Parallax knob allows you to bring these two different images into the same plane, so that any movement of your head out of exact alignment with the optic will not move your point of impact on the target. Many knobs are marked with ranges on them, but most are not precise, just a general guide. The method to adjust your scope to eliminate parallax is to get the rifle solidly supported and trained on target, then run the knob past infinity till it stops, then slowly bring it back while moving your head slightly without moving the rifle. When the reticle no longer appears to float around in relation to target, you are parallax free. This is the best condition to shoot from. Any parallax present makes your aim subject to optical error. For close range shots on big game, some parallax isn't likely to be a deal breaker, but the farther out you go, the more critical it will be, turning a half MOA rifle into a 3MOA shooter at the ultimate moment. Some scopes are calibrated better than others as far as the markings on the knob, but seldom are they spot-on. A few have a moveable knob cover (like your turret knob for zeroing elevation) that lets you set your scope parallax free at a specific range, say 500 yards, then slip the knob to match the 500 yard mark. Still no guarantee the other settings will line up perfectly. I generally set the knob to whatever distance I am using as my base Zero to carry the rifle or make snap shots while stalking. When setting up for a longer shot, where I have had time to lase and dope the wind, one of the steps in the process is always to adjust parallax as described earlier. And the marking on the knob is never exactly what the laser said the range was. Hope this helped some.
FearNoWind
Well-Known Member
Jim and I use the same (or at least similar) technique. I use the yardage indicators on the knob to get me close to where I may need to be and then "fine tune" the adjustment for clearest image and no reticle ghost movement. My parallax adjustment falls into infinity after 800 yards so for anything over that I just run it out to max and adjust back to find the clearest image.
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