Again an old post...and again, what the hell.
I'd say, in the game, assuming it was available? A modified SR-25 in .300 Winchester Magnum. It's lighter than the Barrett M-82(which don't get me wrong, it's long ranged and powerful as hell, but it weighs like a beast), it's accurate, semi-automatic and feeds from a 10 or 20 round magazine that allows quick follow up shots, handling characteristics are similar to the AR-15/M-16/M-4 platform, and the .300 Winchester Magnum does have pretty decent range and packs a punch. If reports out of Iraq were accurate, some SOF members were using this sort of configuration for vehicle interdiction (if someone out there knows more or if this is inaccurate, please let me know).
In real life? Mind you, I have no training as a sniper, but I'd probably pick the same thing assuming I can get it (SR-25 in .300 Winchester Magnum has to be special ordered, if I'm not mistaken). It would just take some time to get used to the recoil, among other things.
However, it seems I voted on the Accuracy International .338 Lapua Magnum for some reason....oops.
