I respectfully disagree with your assessment on ammo. Same gun, same range, and my other RF shooters perform the same with each style of ammo. One thing in common with the foreign ammo tends to be low velocity spreads. That is a very significant factor at distance. The Wolf/SK Standard typically runs in the mid teens to low 20's for 10 shots. CCI SV runs a bit more, typically in the 50's.
Agree that wind is the big issue in this game.