Effect of headwind on verticall?

[broncman]

Graphs look cool, can't say as I completely understand your elevation profile in the first one because the base looks flat to me and not like the elevation profile floor I see at Oak Ridge.

Again ,not sure on the LR target, but I only got ten inches to play with on the LRF and I know what my scores reflected from firing positions 11 and 12 this weekend. I know for a fact that if you pull the trigger with the 100yard flag pointing at you and wind in your face, unless you compensate, you will be sorry. If I am already on the edge of the ten then I only have 5 inches worth of 9...... We all know how little wind it takes just to move a bullet 5 inches.

I do want to learn more about that program. Very cool. Thanks for sharing that. I need to research that program now...

 

[Heman]

It is all how the profile is presented. For example the profile you posted had the vertical in feet and the horizontal in yards but spaced equally making the elevation changes look much greater. If you shrink the vertical by 1/3 the profile looks much different and more similar to what I show.

The elevation profile is adjusted so the horizontal and vertical is scaled roughly the same. Red line shows the straight line and the yellow arrow shows roughly the apex of a 185 Jugs flight at around 2,790 fps (where I run my palma rifle). If you compare this to any of the model shown you will see this is well above any of the turbulence over the hills.

With Oak Ridge you have an optical illusion going on because the trees box the range in and gives the range a deeper drop than what it actually has. While not perfectly flat like Perry or Camp Atterbury it isn't as big of a drop as you think or it looks.

Also to move a bullet 5" in the vertical the wind would have to be constant. The only thing constant in a trajectory is gravity, and that means the wind would have to be blowing awfully hard to have any vertical deviation on the trajectory. Since you're well above any of the disturbance the chances of this are very slim to none.

 

[FatBoy]

I shot next to Sam, Thomas and Bill were on point 7 as well this weekend, and scored one line while Bill, Brian and Russ where shooting.

Toss all the graphs you want out there, a light quartering wind at ORSA WILL throw you out to the 8 ring with a high angle caliber and a mid-ring 9 with a laser. I could see every target in service in my scope and when 9 out of 10 targets get blown out from headwind that is all I need to see.

I used an inclineometer on the range several yes back. about 2.5° from the firing line to the center of the targets. I think the layout where the wind comes up past 600 and then is forced up the 800 (775~ish) yard line Is the culprit. I have seen the 800 and 900 flags almost strait up.

You can use all the science you want and i'll point you to a bumble bee. And then ask how the F a guy with a 22lbs 7RSAUM in a rest had bad shooter position causing his flyer out the top or bottom.

You see elevation shots at AEDC as well but nothing to the degree of Oak Ridge.

EDIT: this may have come across as confrontational and it isn't meant that way. I have only shot ORSA 20-30 times. Much mess than many of the shooters listed in this thread. Bill's thoughts are like gold, as is Russ. That said, they come off scratching their heads some days too. Ask them about the mylar balloon one day.

 

[Heman]

I'd say cheek position on the scope, but I was just going by what Bill has told me and by what the simulation is showing. I'll finally get down there next month for the regional.

 

[FatBoy]

I'll see you there if my on call schedule doesn't change. Love ORSA, and hate ORSA but the matches are ALWAYS ran superbly. . If conditions are normal, we can send that model to NASA to put along side their climate models Sunday afternoon.

 

[Heman]

Well if you shoot F-Class you'll be at the opposite end of the range but I'll see you there. Since I'm running matches at Atterbury haven't been able to get down there as much as I have the past 4 years.

 

[FatBoy]

I sling shoot. We'll be packed in together. Maybe Bill's chrome rifle will blind one of us

 

[broncman]

Kind of joking but serious too... What does your model say when the flags on the six hundred yard line are pointing at each other! Think I have that on video.. The place is crazy at times, but it just leaves you with a more determination to figure it out.

 

[Heman]

What the program does is model various directions and the effects the terrain has on it. Would have to play around and see what angle the wind is blowing to get that. The direction coming straight out does show how your going to have the different directions going on at the 200/300 flags. One would need to plot the wind flags for the range on the map to get what the flags are showing.

 

[wwbrown]

I easily believe there is wind at Oak Ridge that has 2 MPH vertical component to it.

There may be regions along the path of you bullet that has a 2 mph vertical wind but I doubt that the entire 1,000 yards has that vertical wind. If you smoke on the line does the smoke get blown up indicating a vertical wind or does it waft up in the normal way?

I have shot at Oak Ridge and think the range and how the matches are run is fantastic, unfortunately now that my father has moved closer to me I no longer visit TN regularly.

 

[broncman]

2 mph across the whole range? Of course not, but gusty enough in a few places to toss the whole line out at times. Sure, not everyone gets caught by it all the time, but shoot there enough and there is a high probability it will if you do not pay attention.

You are actually shooting right above the flag at the 900 yard firing line and the one on the other side of the 800 berm. When they are pointing straight at the 800 and 1000 yard firing line berms, where do you think that wind goes?

You are welcome to pull the trigger all you want in those conditions.

My scores at Oak Ridge on the LRF target drastically improve when I pay more attention to those flags and the quartering winds.

We have probably beat this to death so I will not clog up this thread with Oak Ridge beliefs. I had a great time their this weekend and was very surprised at the results for Fclass Larry sent out last night.


Question? If it is not a wind, then explain why at times, almost the whole line will jump out the top, usually after a good run. Bad shooter mechanics for the whole line?
Ken