Wind is going to get you, but these matches are won and lost on your hind legs. 25% of a normal 80 shot high power match is standing. 40% is rapid fire at 200 & 300 where wind isnt going to get you near as much as your posistion.
20% is laying on you belly shooting slow fire at 600 yards. You can chase spotters (which I'm against) and beat your off hand scores.
Frankly not many of us can practice 600 yard shooting. We just don't have the ranges available plus someone to pull targets for our practice. So learn the fomula (angle of flag / 4 - Velocity) and mid range flags to devermine wind speed, And R*V/10 to make your wind corrections. Not perfect but close. (Range in 100 yards times wind velocity divided by 10 = number of MOA corrections for full value wind)
Then use 100 yard reduced targets to work on offhand and rapid fire. Spend most of your practice off hand, thats where you'll loose most of your points. Dry fire the heck out of your rifle.
Rapid fire is nothing more then a good position, NPI, and followthrough. You can get that by slinging up and watching TV over your front sight.
Don't underestimate the value of practicing with 100 yard reduced targets.
Something I use to do to work on my Offhand during the winter was shoot cast bullets at 50 Ft NRA Small bore targets at a 50 Ft indoor range.
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071