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Lance1
February 27, 2009, 09:43 AM
I need to zero my scope and it seems to be always windy. I have found a calculator to figure drift but I don't understand the data they are asking for. http://www.biggameinfo.com/index.aspx?&page=%2fbalcalc.ascx

Is there a laymen way to estimate the drift?

How about a different angle to this question; at 50 yards in a 10 MPH wind side, how much will a .22 drift?

36 grain hollow point, 1280fps muzzle, 131 ft lb at muzzle

L_Killkenny
February 27, 2009, 10:42 AM
Where I live it blows all the time. Somedays it's only 10MPH but usually more.

What you are trying to do is impossible. You'll never sight in the left/right on a .22 at a "zero range" of 50 yards or beyond in even the slightest breeze. Wind changes ever second and it's impossible to get an accurate reading on what you are doing. You can do it with a fast moving centerfire rifle because with drift at 100yards is far less. Even then it can be tricky and you're better off waiting for better conditions.

Sight in your .22 at 25 yards or less on a day when the wind is blowing as little as possible or in a protected area. Try sighting in with the wind or against it. The wind will also tend to slow down at dusk. Once you are sighted in 25 yards you can move the range out to your disired zero and adjust your up/down but DON'T TOUCH the windage. Truth be known, if you sight in your .22 at 25 yards period you are good to go out to any range you should be shooting a .22

L_Killkenny
February 27, 2009, 11:03 AM
Ran the numbers thru my ballistic program. If you sight in at 20 yards you will have a "maximum point blank range" (MPBR) on a 2" vital zone of 85 yards. BTW, that 20 yard zero = 75 yard zero. In a 10MPH wind your drift is still .68" at 20 yards. If you tried to sight in at 75 your wind drift is 3.65" and your MPBR is 4.51". See why it's easier to do it a 20 or 25 yards? Even though your range only increased 3.75 times(75/20), your drift increased 5.4 times.

SIght in short then check it at distance

Lance1
February 27, 2009, 04:58 PM
Thank you L Killkenny, your information was allot of help. I lucked out and had some low wind this morning. I zeroed in like you said at 20 yards, pattern at about an inch (using a holding fixture). Then put the target out to 50 yards, with wind and hand held and could hold within a foot, hey, I'm a lousy shot in the first place.

Also thanks for the wind drift info, that is what I was looking for.