wind affect

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albow
.257 Roberts
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wind affect

Post by albow »

Just wondering at which stage in flight is your bullet most affected by the wind in long rage shooting.

I have heard that it is over the initial part of the flight however I would have thought that further down range as the bullet's velocity drops off would leave it more affected.

Thoughts / knowledge on this and can you explain it?
Blackpete

Post by Blackpete »

Hi Al,
the way this was explained to me is; at the beginning of the bullets flight only a small amount of distortion is needed to create a large amount of drift at the target. Like you, I first thought the bullet would be most vunerable at the end of it's flight where it is slowing down, but this is wrong.

If you get a piece of paper and draw a straight line from the bottom of the page to the top, then draw another line (starting at the same point at the bottom of the page) and running off to the right at say two degrees, from the bottom to the top, and see how far the other end of the second line ends up away from the first, now imagine the differance at 500m.


So as you can see you only need a slight shift in direction at the start of a bullets flight to end up with a large differance at the target end.

Pete.
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albow
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most important flags

Post by albow »

Pete, thanks for the explanation with the lines. That made it very easy to understand.

Based on this then it will be more critical to get the same "read" on the flags for the first couple of hundred yards then at the far end?
Blackpete

Post by Blackpete »

Absolutly mate,
i'm no expert on the wind subject but I do watch the first few flags a little more, having said that you still need to keep an eye on the others especially that one in the gully. If you're out there tomorrow your best bet is to see Tony & Jr and ask them what they do as they have been doing it longer and better than me.

Pete.
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Ned Kelly
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Post by Ned Kelly »

G'Day all,
I seem to remember reading that if you break the distance from rifle to target into 1/3's and judge the wind in 3 parts it helps judging the total wind effect over long range. I'm not sure but I think it was Dave Tubb who wrote this on one of the Yank LR web sites.

But essentially, if I can I'll walk the range to feel the wind I can gain a better appreciation of where the wind is strongest and see where it is being channeled by trees, gullies etc. and yeah the wind in close is very important during the early stages of bullet flight.

Cheerio Ned
Tony Z
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Post by Tony Z »

After my effort on Sunday, i am certainly not the person to ask about wind reading. What i can tell you is that the die has been cast early for our 600 IBS in that the 200 SMK in 30 cal and the 168 SMK in 7 mil are running away with the group and score aggs. If the targets are any indication of things to come, Pete, Eric and Bob N should go to Fly matches and blur their scopes so as to not see a bullet hole. It is quite obvious that seeing your fall of shot creates tail chasing that is destructive to both score and group. Their results superimposed over a Fly target are great scores, with all averaging over 50 including group score.

Tony Z.
Rinso
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Post by Rinso »

Tony Z,
If the targets are any indication of things to come, Pete, Eric and Bob N should go to Fly matches and blur their scopes so as to not see a bullet hole. It is quite obvious that seeing your fall of shot creates tail chasing that is destructive to both score and group
Interesting observation Tony, also one that I tend to agree with, as far as seeing fall of shot not always being an advantage.
I have been guilty of chasing wind, as have we all, seeing your fall of shot is only a good thing when your bullet lands where you expect it to.

All the times I have fired a first round which was wide of my expected impact area I have struggled to make a good score on that target, the tendancy to start second guessing things becomes overwelming at times and reduces confidence, once you lose confidence in what you are seeing in the flags the whole show goes up a few degrees of difficulty.

I believe that small calibres like the 6BR & 6.5's have an advantage in this area, as those shooting them dont have to doubt what they are seeing until after the target comes back.

Then again when the first shot lands in the 8,9,10 ring knowing your on the money is a great asset.

All good fun really isn't it.

cheers
Dave P
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