Well think that in the rimfire.. wind gives the faster projectile something to "lean" on.. so in essence, is the reason that it might shoot better in the wind.. i have noticed this with Federal UM719. It is also said that when there is no apparent wind (Lance Dement whom says "There never ain't nothin'!"), to use the slowest thing you have!Ok, got it. Then my next question is how is ammo sorted for different shooting temps and wind. I would think that on a windy day a faster bullet could minimize drift. Or is it the burn rate of different ammo powders? I read somewhere that a specific top shooter has a variety of ammo that he may change from card to card as the match progresses. What is the variable that a shooter is chasing in ammo?