Paralax

[arse]

I have read a couple of articles about parallax and still can't turn it in to common sense.  Does anyone have a common sense explanation of parallax and more importantly what does it mean to me.  Currently, all of my scopes are 3-9 by 40's and can can hit consistently (10" circle) to 400 yards with my Savage Model 10 predator.  I have always thought that going much over 12 power will get you into need parallax adjustments.

I would love it if someone could give me a common sense explanation.

Thanks....Andrew

[coyotehunter_1]

Arse,

Maybe this will help a little?


Source: http://www.burrisoptics.com/SFAQ.HTM#18
What is parallax ?
Parallax is a condition that exists when either the reticle or the image is not focused precisely together . This can create the effect of the crosshair appearing to move when you move your head side to side or up and down.

How can I tell if I have a parallax problem ?
From a solid rested position, such as a benchrest, line your scope up on a target as if aiming to fire a round . Remember to keep the scope in a solid position . Carefully note the position of the crosshairs . Move your head up, down, and side to side . Should you see the crosshairs move off target, while moving your head, you have parallax . Unless you position your eye in exactly the same location from shot to shot, you can experience sligh point - of - impact shift and larger group sizes . .

Should I be concerned about parallax and why ?
There are two separate lines of thought in regard to parallax due to the small variations in values . One is the line of thought from the big game hunting standpoint and the other is from the target shooting and varmint hunting standpoint . In big game hunting situations, where intended targets are larger and yardages are not excessive, minimal parallax is not a concern . In target shooting, when attempting to place one bullet on top of another and in varmint hunting situations, a shooter has need for concern . When using the high powered scopes associated with these types of shooting disciplines, parallax error can decrease accuracy . The amount of accuracy loss can be directly tied to the amount of parallax error that exists.

[Hawks Feather]

Another area where this comes into play is when you are using a scope made for a high power rifle on a .22LR.  The parallax is usually set for 100 yards and when you start shooting the .22 (usually at shorter ranges) it can affect your accuracy.  That is the reason that Burris, Leupold, and some others make specific scopes for rim fire.  The parallax is set for a shorter sight pattern.  Burris will change the parallax on one of their scopes if you send it in.  I don't know what it costs now, but it used to be $15.00.  I had a 2x7 that I wanted to use on rim fire and had them change it for me.  For the most part, most hunters will not notice the difference.  It is sort of like accuracy, a half inch to a benchrest shooter is terrible, but to a groundhog hunter it is a kill.

Jerry

[vvarmitr]

I have always thought that going much over 12 power will get you into need parallax adjustments.

The added power magnifies the movements making it more noticeable, but it is the same amount of movement whether you're at 3X or 24X.

Another thing about the higher powers ...
Ever notice the shadows in the scope when you don't have the proper eye relief or when you move your eye off from the center of the scope?  As you go up in power eye relief becomes more critical or shall I say has a smaller sweet spot where you can put your eye from the lens. Same goes w/ being centered.

Parallax adjustment makes the target more defined (in focus) so you know right were you're aiming. W/o the adjustment at ranges other then what the scope is set for; the target is fuzzy, though you may not be able to tell because of the distance, you are aiming at the fuzz rather then being pinpoint.  Does that help?

[arse]

Thanks for all the help.  Now it make common sense to me.