I am trying to learn how to shoot F-Class on my own. I want to know how much of a hold off is needed for a 10 mph 90 degree crosswind at 550 yards with a .308 Berger 175gr Match Target BT Long Range bullet at 2600 fps assuming a 100 yard zero. According to JBM Ballistics its 20" of wind drift. Does that mean its a 20" hold off of the bullseye? Just seems like a lot to me.

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