Wind at 100yards

[Jenks]

I don't pretend to be a good shot rather thinking of myself as very average, some days I do really well other days not so good. I have a (stalking) chum who I would describe as a very good shot. I took him to Bisley, we were shooting at 1000x. the wind was pretty tricky, pretty erratic strength wise coming mostly from behind, and fish tailing. The flags were all over the place. We were both shooting Blasers mine the LRS2 in 6.5x55se, with a heavy fluted match barrel his rifle was his standard Blaser Offroad with a light barrel in 308win'
My rifle was pretty well set up and I was into the bull with the first shot. His first shot was on the screen but only just. He made a couple of adustments and proceeded to match me almost shot for shot. When we took a break I asked him how he did it saying that I thought the wind was pretty tricky, he replied ''Dunno I don't think about it I just get down and shoot it.'' He really meant it. I know for a fact that he had never shot at a range greater than 300x ish before. Ok he would probably never win a major competition. But I wouldn't bet against him. I think what I am trying to say is is is possible to get bogged down with the theory. Sometimes maybe it's better to just get down and 'Shoot it'.


Jenks

[Dougan]

another thing someone told me, and i don't know how true it is is that the bullets go round like this (see attachment)....

I'd imagine its possible due to the spin, but surely it wouldnt be accurate if it did this? obviously I've exagerated it in this picture as it might not be noticable at 100 yards, but over 1000 yards, would a bullet spiral like this?

I've been told about this aswell - as you've said, the picture is exagerated, but the bullet does travel in a spiral - I was also told, that the spiral expands out to a point, then comes back in to a 'sweet spot', and then expands out again. And is (partly) why most TR rifles have 1/13 turns. Some people prefere 1/14 for short range (brining the point at which the spiral closes down forward), and 1/10 for long range. This could all be rubbish (and I'll soon find out), but my TR rifle (1/13) shoots better groups at 600, than it does at 300, and I think it is due to the 'spiral effect'.

You'll get the hang of the wind easyly enough - for the basics, use a chart and the flags - this is an old wind and elevation chart, that is still relevant for RG ammo:

In detail, the wind is complicated though - If you can interpret (also retrospectivly) the conditions you see/measure down the range, then someone like yourself (a computer bod) might get value from some of the balistic software available.

From what I've seen though, a lot of it is down to experience... and some of the best shots at Bisley, know how the wind behaves in different conditions at specific places on the ranges.

[TattooedGun]

another thing someone told me, and i don't know how true it is is that the bullets go round like this (see attachment)....

I'd imagine its possible due to the spin, but surely it wouldnt be accurate if it did this? obviously I've exagerated it in this picture as it might not be noticable at 100 yards, but over 1000 yards, would a bullet spiral like this?

I've been told about this aswell - as you've said, the picture is exagerated, but the bullet does travel in a spiral - I was also told, that the spiral expands out to a point, then comes back in to a 'sweet spot', and then expands out again. And is (partly) why most TR rifles have 1/13 turns. Some people prefere 1/14 for short range (brining the point at which the spiral closes down forward), and 1/10 for long range. This could all be rubbish (and I'll soon find out), but my TR rifle (1/13) shoots better groups at 600, than it does at 300, and I think it is due to the 'spiral effect'.

You'll get the hang of the wind easyly enough - for the basics, use a chart and the flags - this is an old wind and elevation chart, that is still relevant for RG ammo:

windage 006.jpg

windage 009.jpg

In detail, the wind is complicated though - If you can interpret (also retrospectivly) the conditions you see/measure down the range, then someone like yourself (a computer bod) might get value from some of the balistic software available.

From what I've seen though, a lot of it is down to experience... and some of the best shots at Bisley, know how the wind behaves in different conditions at specific places on the ranges.

I have that exact wind chart in my bag, and it came fairly close when I shot at oxford.

I think as I've shot fullbore a total of 3 times now (its easy to get hooked), that i still have bundles to learn...

It's not as easy to get range time here, and I lack funds to purchase more reloading bits (bullets and powder) for the rest of the month, But i shall try and get out and put some practical work in on the range.

I know practise makes perfect, and the way i learn best is by doing... but i dont have a range outside my house, so theory wil have to do...

atleast if i understand what the wind is doing and why my bullets are going where they are going, i might have a good idea how to correct it :)

[Dougan]

I totally sympathise about the frustration of not being able to do as much shooting as you want - I'm v lucky that I have a fairly local range where I can shoot 200 yrds 7/8 times a year. I also go to Bisley 8/10 times a year (travel up from Dorset)...but there is a limit to how many times I can afford to go. The good thing about this sport is that you can shoot into old age - so there's no rush.

I use that chart to judge the wind (but take my zero from previous score cards), and my first sighters are usually close enough - I have found that with the ammo (ruag) I'm using I can take a half to a full minute off the numbers on the chart. e.g on the chart it shows an increase in elevation from 300 - 600 is 10 1/2 min, but for my rifle and ammo it's just under 10 min.

This is particlarly handy as on my front sight (which is exactly the same as yours), each 'notch' equates to 5 min - So when moving from 300 to 600, I only have to drop the front sight 2 notches..and it's pretty much there.


btw: there's another post about 'plotting' on scorecards (I think it's in 'competative shooting'), that you might find of interest....

[ovenpaa]

It took me a while to use plot sheets in a manner that would give meaningful information but once done the data is incredibly handy and I find I can go back and analyse a competition the following days plus add the data to my drop sheets.

Well worth getting your head around.

[TattooedGun]

I totally sympathise about the frustration of not being able to do as much shooting as you want - I'm v lucky that I have a fairly local range where I can shoot 200 yrds 7/8 times a year. I also go to Bisley 8/10 times a year (travel up from Dorset)...but there is a limit to how many times I can afford to go. The good thing about this sport is that you can shoot into old age - so there's no rush.

I use that chart to judge the wind (but take my zero from previous score cards), and my first sighters are usually close enough - I have found that with the ammo (ruag) I'm using I can take a half to a full minute off the numbers on the chart. e.g on the chart it shows an increase in elevation from 300 - 600 is 10 1/2 min, but for my rifle and ammo it's just under 10 min.

This is particlarly handy as on my front sight (which is exactly the same as yours), each 'notch' equates to 5 min - So when moving from 300 to 600, I only have to drop the front sight 2 notches..and it's pretty much there.


btw: there's another post about 'plotting' on scorecards (I think it's in 'competative shooting'), that you might find of interest....

Yeah, the front sight is something I'm yet to master... I realise its 5 mins per notch, but i'm still trying to get y head around the elevation at different distances to begin with...

I think once i have them all down I'lkl be able to set them via the front sight for the major jumps,a nd tweak with the rear sight, and hopefully have my cheekpiece set in almost the same position throughout the different ranges...

What i want to get made however, is a nit with a grippy thread I can use to set my cheekpiece as at the minute having to use an allen key is frustrating at best...

dreams of this stock for future (maybe in 5 or 10 years...) haha


http://www.robertsoncomposites.com/stoc ... et/bc1.php

with a magnetic cheekpiece... oooh, that'd be nice!

[barney57]

Wind makes a difference at any range.

It makes quite a difference if it is gusting as opposed to just constant.

Ideally work up your rounds in still weather.

And what if the wind at any strength is Oblique??

[TattooedGun]

Wind makes a difference at any range.

It makes quite a difference if it is gusting as opposed to just constant.

Ideally work up your rounds in still weather.

And what if the wind at any strength is Oblique??

Oblique is any angle that is not a multiple of of 90 degrees...

so a 45 degree wind would be considered oblique - so it would still affect the bullet..

A straight angle however either straight at you or straight at the target would be interesting, although i would hazard a bet that towards you would make the bullet hit low and away from you would make the bullet hit high, albeit inline (Zero'd) horizontally...

[ovenpaa]

Christel has a handy chart that shows the impact wind has on he point of impact, hopefully she will find it and post it up.

[Dangermouse]

The difficulty I have is trying not to think 2 dimensional when wind is concerned.

With everything that is going on, the bullets flight can also be pushed up wards or down wards as well as side to side and any diagonal combination of everything in between.

We saw this very dramatically at the F Class long range comp where by even with no wind the heat or thermals on the day was sending bullets all over the targets.

Even the F Open guys with their fast and heavy rounds were given a wake up call,

DM