Rimfire Wind Charts are unreliable for diabolo air rifle pellets.

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"Bwalton"On that 75yard GS shot when I said that I am going to put it on dead zero meaning that I was not going to hold over for wind, but It was 1.5mil hold over for vertical.
I am just trying to understand exactly what my rifle is doing, be it right or be it wrong for some crazy reason from all the practicing it works lol
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I have watched the new video and in particular the wind indicators. Unfortunately there is only a glipse of getting both flags and shots in the same frames. But it seems obvious to me that when the wind was moving the pellets left (red flag) the pellets are averaging a lower POI than when the pellets hit to the right (white flag) . Here is the one I captured when the second or third pellet struck left when shot on the red flag (flag in lower left of the picture).

I have put a yellow line of best fit in to show that the red flag (R to L wind) is pushing the pellets left and lower than that shot on a white flag to the right - even though the white flags are averaging more towards 10:30 O'c than 9:00.
That target shows exactly the trend I am writing of.

When you are judging holdover on mildots in the hunting field, rather than clicking from a known perfect zero to a known target zero and adding or subtracting for the wind lift, it well may be you are computing all this into the equation. 
Just keep knocking those pests over! ... Best regards, Harry.
 
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"Yrrah"
"Bwalton"On that 75yard GS shot when I said that I am going to put it on dead zero meaning that I was not going to hold over for wind, but It was 1.5mil hold over for vertical.
I am just trying to understand exactly what my rifle is doing, be it right or be it wrong for some crazy reason from all the practicing it works lol
Click to expand...
I have watched the new video and in particular the wind indicators. Unfortunately there is only a glipse of getting both flags and shots in the same frames. But it seems obvious to me that when the wind was moving the pellets left (red flag) the pellets are averaging a lower POI than when the pellets hit to the right (white flag) . Here is the one I captured when the second or third pellet struck left when shot on the red flag (flag in lower left of the picture).

I have put a yellow line of best fit in to show that the red flag (R to L wind) is pushing the pellets left and lower than that shot on a white flag to the right - even though the white flags are averaging more towards 10:30 O'c than 9:00.
That target shows exactly the trend I am writing of.

When you are judging holdover on mildots in the hunting field, rather than clicking from a known perfect zero to a known target zero and adding or subtracting for the wind lift, it well may be you are computing all this into the equation. 
Just keep knocking those pests over! ... Best regards, Harry.
Click to expand...
Thanks Harry. Very informative post. Have this bookmarked for my future ref. 
 
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Harry,

Thanks for replying.

I was guessing that the Piledrivers might act more like bullets. As for the other pellets, when you're dealing with wildlife control and getting paid by the animal, you need to make sure that you can recover it while not recreating safety issues and certain pellets help with this more than others.

As for the headwind, here is why I asked the question (bear in mind that I am a novice in terms of wind and ballistics). Shooting my Air Arms S400 .177 from a bench rest into a 10 - 14 mph wind at 40 yards will both raise and lower the diabolo pellet for me and move it to the left. This is happening at what I consider to be sort range so to help paint the picture of where I'm shooting, I have a house 3 yards behind me, woods to the left, open field to the right, and a wooded sloping area (25 - 30 yards long, 30 ft high) with a 6 ft wide path cut into it behind the target. Is it possible I'm getting these mixed results from the wind blowing down the slope so it isn't really a head wind but something else, would it be more that the landscape is creating a bunch of multi-directional winds each doing it's own little thing, or something else?

Thanks.

Eric
 
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"WCT_Editor"Harry,

Thanks for replying.

I was guessing that the Piledrivers might act more like bullets. As for the other pellets, when you're dealing with wildlife control and getting paid by the animal, you need to make sure that you can recover it while not recreating safety issues and certain pellets help with this more than others.

As for the headwind, here is why I asked the question (bear in mind that I am a novice in terms of wind and ballistics). Shooting my Air Arms S400 .177 from a bench rest into a 10 - 14 mph wind at 40 yards will both raise and lower the diabolo pellet for me and move it to the left. This is happening at what I consider to be sort range so to help paint the picture of where I'm shooting, I have a house 3 yards behind me, woods to the left, open field to the right, and a wooded sloping area (25 - 30 yards long, 30 ft high) with a 6 ft wide path cut into it behind the target. Is it possible I'm getting these mixed results from the wind blowing down the slope so it isn't really a head wind but something else, would it be more that the landscape is creating a bunch of multi-directional winds each doing it's own little thing, or something else?

Thanks.

Eric
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Eric, I think you have the makings of a very complicated airflow on your range.

My suggestion is to get at least 5 good wind indicators for a 50 yard range. Position them with the nearest no more than 5 yards from your muzzle and far enough to the left (right hand shooter) such that the other four can be spaced converging to the target in such fashion that with both eyes open you can see all flags with the left eye and your sight picture with your shooting eye. ... The height of the top of the indicators should be just under your line of sight to the target.

Sight in the rifle for the POI you favour. Sit and watch the flags for five minutes then choose what you feel to be the most consistent flag/ breeze orientation. Then with sight for a shot and with both eyes open wait for the chosen condition and ease off the shot.
After some sessions you will begin to get the feel of your wind patterns. Then you can begin to experiment choosing different pattern sets to see the relationship between the particular wind/flag orientation and the PsOI of your pellets.

There is really no shortcut to learning . Try to be objective to the extent of discarding emotional attachment to the results. Be a disinterested bystander whilst performing your tasks as best you can.

If you have a front BR stand and rear bag with ears, you can set up the aim then just watch the indicators. Trigger your shot before the flags begin to sag. Don't try to get an extra shot as the flags begin to change as their change reaction is following the wind change and you will get caught with too much or not enough hold off.

If you can somewhat master your wind conditions on that range you will be good to go and shoot on most other ranges.
I look forward to reading of your progress in some weeks or month's time.
Best regards, Harry.
 
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These charts were designed for RIGHT hand barrel twists and are basically an estimate of what happens, they are not the Bible.

The effects shown in these charts vary much depending on the how tight the barrel twist is, tighter barrels (lower twist ratios) are more prone to follow these charts but Air gun barrels are by nature not tight, the required twist for stabilizing such a short projectile can be close to 20:1 and I have even seen barrels approaching 30 to 1...In these cases the charts are not only not accurate, they seem to be ridiculous...

We should take them as a guideline and adjust them to the specifics of our gun barrels....

AZ 
 
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"azuaro"These charts were designed for RIGHT hand barrel twists and are basically an estimate of what happens, they are not the Bible.

The effects shown in these charts vary much depending on the how tight the barrel twist is, tighter barrels (lower twist ratios) are more prone to follow these charts but Air gun barrels are by nature not tight, the required twist for stabilizing such a short projectile can be close to 20:1 and I have even seen barrels approaching 30 to 1...In these cases the charts are not only not accurate, they seem to be ridiculous...

We should take them as a guideline and adjust them to the specifics of our gun barrels....

AZ 



I agree some barrels can be loose, but we have to keep in mind that many barrels now a days are choked. And as with chairgun and most things these are only a reference, Thats why I base my finding in the real world... according to my rifle.

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