Magnification has no effect on parallax.

Maximum ParallaxError (millimeters) = 0.5 d (ABS(t-p))/p
d= objective diameter (mm)
t = target distance (yds)
p = fixed parallax setting (yds)

more information:
http://www.rimfirebenchrest.com/articles/parallax.html

edited to add units of measure.

Last edited by Grady8541; 03/28/16.
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