wind at 200 yards?

[uchi]

so you're saying you missed a 10mph gust?

nope i didnt say that, i said i knew there was a decent wind but didnt know how fast it was moving. i didnt have my wind gauge with me nor did i have my ribbon flags set up otherwise i would have figured out the angle and strength they were floating at did some quick trig multiplied it by PI and subtracted 12 and figured out it was a 10.7mph wind

 

[uchi]

The wind at the firing line is more critical than the wind at the target. If the wind is gusting, choose to either shoot in the lull or the gust. If the wind is swapping directions, try to predict when there is a neutral wind and shoot on it. If I understand the description of your range correctly, the high sides could result in very turbulent air on the range which could be tricky to figure out.

If you don't have a wind meter, get the wind from your local radio station, or use a wind flag. If there are wind flags at the range, divide the angle between the tip of the flag and the flag pole by 4, that will give you the wind speed in MPH, and is useful up to about 25 mph in which case the flag will rize above the horizontal; a wind above 25 mph is too difficult to read by the flag. A field expedient wind flag can be made by holding a rag at shoulder height with your arm fully extended. Let the rag go and point to the spot where it hits the ground. The angle between your arm and your body is dived by 4 to determine the wind speed in mph.

To determine your bullet's drift with a .308 or a .30/06, divide the range by 100 and mulitply by the wind speed in mph. Divide this number by 15 to determine your drift in MOA. As range increases beyond 500 yards the constant is reduced by 1 for each 100 yards of range. But in your case, with a 10 mph wind and a 200 yard target, 2X10=20, 20/15=1.3 MOA, 1.3@ 200= 2.6".

thanks for the explanation and help reading the flag. hopefully next time i go if there is a strong enough wind the range flag wont be half frozen and ill be able to use your info to help me make adjustments. im gonna write down your formula and leave it in my range bag along with some other info i keep in there to help me shoot.

id like to think the wind was being tossed everywhere having to deal with the side berms and back stop berm. it was starting to pick up while we shot clays early and was throwing them around pretty good.
im just waiting for my order of bullets to arrive although ive got the day off so i may just go look around for some and get some more loads and get out and try again

 

[FTRRookie]

it was more a drop than anything. the bullet was only about 1 inch off center but had dropped about 2.5 inches.

alright in that case it makes sense to have gotten random shots hitting that low

I'm certainly no expert, but isn't vertical typically ammo related? If you changed your load from the one you had success with at 100y it could simply be the difference in the load and not wind at all. I'd say go back to the load you shot well at 100 (1/2" IIRC), and try that at 200. At least you know it's a good load for your rifle.

 

[skypilot]

alright in that case it makes sense to have gotten random shots hitting that low then, better luck to me next time

You don't need luck, just the fact that you are willing to ask shows that you are much better than just a lucky shooter.

 

[uchi]

I'm certainly no expert, but isn't vertical typically ammo related? If you changed your load from the one you had success with at 100y it could simply be the difference in the load and not wind at all. I'd say go back to the load you shot well at 100 (1/2" IIRC), and try that at 200. At least you know it's a good load for your rifle.

thats possible unless the berms were causing the wind to press down as they were coming in. ill try the other loads i used next time i head out and see if i have better luck with them along with some following this same powder load and see how well i do on a day with no wind

 

[uchi]

You don't need luck, just the fact that you are willing to ask shows that you are much better than just a lucky shooter.

thanks, this is a constant learning experience and the more im doing it and now that im reloading the more there is to learn.

 

[Toolman]

, and since i forgot my rear bag at home i used my plastic ammo box to stabilize the rear of the gun.
i didnt even think about this but ive got a box of factory ammo in my range bag i should have shot to compare it to.

i knew there was a decent wind but didnt know how fast it was moving. i didnt have my wind gauge with me

I take it you are doing load development? Doing it 10+ mph cross winds is not the preferred method.

Preparation is where its at, have everything you need with you each time and if possible wait for a calm day.

see how well i do on a day with no wind

Good idea.

 

[Tikka223]

The wind at the firing line is more critical than the wind at the target. If the wind is gusting, choose to either shoot in the lull or the gust. If the wind is swapping directions, try to predict when there is a neutral wind and shoot on it. If I understand the description of your range correctly, the high sides could result in very turbulent air on the range which could be tricky to figure out.

If you don't have a wind meter, get the wind from your local radio station, or use a wind flag. If there are wind flags at the range, divide the angle between the tip of the flag and the flag pole by 4, that will give you the wind speed in MPH, and is useful up to about 25 mph in which case the flag will rize above the horizontal; a wind above 25 mph is too difficult to read by the flag. A field expedient wind flag can be made by holding a rag at shoulder height with your arm fully extended. Let the rag go and point to the spot where it hits the ground. The angle between your arm and your body is dived by 4 to determine the wind speed in mph.

To determine your bullet's drift with a .308 or a .30/06, divide the range by 100 and mulitply by the wind speed in mph. Divide this number by 15 to determine your drift in MOA. As range increases beyond 500 yards the constant is reduced by 1 for each 100 yards of range. But in your case, with a 10 mph wind and a 200 yard target, 2X10=20, 20/15=1.3 MOA, 1.3@ 200= 2.6".

Would you happen to have a similar formula for .223 Rem? I don't think I've heard of this system of estimation. I like to try it but .308 isn't my caliber.

 

[uchi]

I take it you are doing load development? Doing it 10+ mph cross winds is not the preferred method.

Preparation is where its at, have everything you need with you each time and if possible wait for a calm day.




Good idea.

yeah i am, i brought 5 different loads out the previous time and found one that worked so i made a small adjustment to it and took a chance to see if it would help or not. when we left my place the day was fairly calm so we shot some clays first and halfway through that things picked up a little, but since we were there we figured we'd shoot off the rifle as well just because we were there. i didnt think the wind would have that much affect on the bullets at only 200 yards.

 

[savage.3006]

Read what Gerry wrote (Mystic Precision). If the wind was blowing hard enough to blow over the outhouse think about what its doing to your bullet inside the berm walls? A constant wind is better to shoot in then a wind caught in between berm walls because it doesnt know what it wants to do.

 

[Boomer]

Would you happen to have a similar formula for .223 Rem? I don't think I've heard of this system of estimation. I like to try it but .308 isn't my caliber.

Pull up the JBM table for your load, then simply adjust the constant to match the wind drift in the tables. That will get you close when you're at the range or in the field.