I think the 6DOF does, Sam and Harold Vaughn are the only ones I've heard that use it though. Harold says it's pretty complicated, but I bet I could figure it out with enough time, which I have way too much of lately. [img]images/icons/grin.gif[/img] Sam must know a little more about computers than he lets on, ya think? [img]images/icons/wink.gif[/img] [img]images/icons/grin.gif[/img]
I'll try the best I can.... I shoot at williamsport. Last year was a rather windy one. In fact, by looking at the scores and group aggs at the end of the year as compared to the last several years, I would say the worst year in the last 6 or 7 though I've not shot there during those. The world open was shot in a hurricane morning to night both days.
We have on average about 110 shooters each Saturday and Sunday. In EVERY group I looked at all year long when someone had pronounced wind effect (given it was someone with a gun that actually shoots) the shot/shots that blew out of the group went low right or high left, and at approximately a 15 degree angle from horizontal. Now, I'm not gonna get into a equasions war with anyone and I'm sure as hell not gonna go try to scientifically prove the angle to be 15Deg, 0 Minutes, 0 Seconds.
In a right twist barrel your bullet is turning clockwise as viewed by the shooter. Just like a pitcher throwing a pitch that curves, it is the air pushing harder on one side of the ball that provides the mass to disuade the ball on its path. Well, your bullet is spining down on the right side, that means the air "pushes Up". If the wind comes from the left, the air pushes the bullet down. Yea Yea Yea, the bullet is pitched a little also, nose up, and yawed slightly, whatever. Go shoot paper at 1000 in varying wind waiting a while between shots and see where your group forms. If I had a digital camera, I'd send ya photos of targets, perhaps Darryl can send ya some. he's probably got lots. Although, since he has some weight up there, he probably never has to shoot the relays with wind!
Many people up there like to think that wind has a recognisable vertical component that "Blows" the bullets high or low. Some think headwind and tailwind cause the vertical thay see. Well, I basically I think that my handloading sucks as compared to some of the shooters up there and my gun doesn't work as well, so, I'm not gonna blame the air. If your gun shoots 10", and you shoot in a wind, Your group WILL BE within a 10 inch band across the paper.
Lets see the flames fly from this one!
If you have something that you disassemble and reassemble enough times, sooner or later, you'll have two!
Do you have a copy of Harold Vaughn's book "Rifle Accuracy Facts" already? If you don't I suggest you get your hands on a copy, you'd love like it alot. It has a way to test what the vertical component actually is with your bullet. I won't bother if you already have read it though.
15 degrees from horizontal is close to his example, his was 17 deg for a 68gn 6mm match bullet with a GS of 1.38 (gyroscopic stability factor) at sea level.
To give you a little example, he shot a group at 200 yards with wind at varying intensities coming from 3 o'clock to produce a line of impacts from the wind drift that stretched right to left the harder the wind blew. The group looks to be in the order of an inch and a half, but, also the harder the wind blew, the higher the shot impacted because of the vertical component. It has alot to do with the GS, wind speed and range. The higher the wind speed and or the higher the GS and the longer the distance the more vertical wind drift component will be.
I can post a pic if you like to show you an illistration if you haven't read the book and seen it yet?