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Wind affect on groups?


rvb
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Shooting 25yd groups today in 20mph sustained (30mph gusts) winds, blowing 90 degrees left to right. 9mm 147s at 930fps. I struggled freestyle due to the wind and my groups were right of center. I decided to shoot off a bench. I called good shots, and was very happy with my group size (2.3" from a Glock 34), but it was 4" right.

Could the wind really push them that far in just 25 yds? Or more likely trigger control or poor grip on the rest?

Sights don't appear to have moved, and I always thought that they were dead on (previous 25yd freestyle groups were dead on).

I have little experience in the wind (part of why I went out today and spent some time w. the 10/22). More experienced opinions welcome!

-rvb

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Wind moves the shooter more than it moves the bullet, but it does move both.

I'd bet on this one.

I'd also think it possible that, as the cross wind is blowing, that you might be altering the muscle tension in your stance/grip to compensate in staying on target. While the sight picture may not have changed, perhaps the gun's movement in recoil will, and it might affect POI.

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I entered this into Hornady ballistic calculator using the provided info for MV and a ballistic coefficient of .5, from left to right at the maximum speed of 30 mph, it yields .5" shift at 25 yds and 1.0" shift at 50 yds. For 20 mph it was .3" and .5".

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I entered this into Hornady ballistic calculator using the provided info for MV and a ballistic coefficient of .5, from left to right at the maximum speed of 30 mph, it yields .5" shift at 25 yds and 1.0" shift at 50 yds. For 20 mph it was .3" and .5".

Just thought to plug the info into a ballistic calculator. It's showing 1.5" off for a 25mph wind. Looks like it was a combination of wind and me....

-rvb

1.5" ?! As my Garmin would say . . . recalculating!

I plug 30 mph at 90* into http://handloads.com/calc/ and it comes up to 1.86" at 25 yds ......

:wacko:

-rvb

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Wind moves the shooter more than it moves the bullet, but it does move both.

+1

This is not handgun related, but the same thing happened to me with an AR @100. all sighted in, winds picked up to a nice 20mph with 30-35 gusts, I shoot 10 rounds, great elevation sub moa but 8" l-r on either side of the X. I over compensated for the wind and didn't realize. Don't fight the wind is what I learned from that outing.

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