Can anyone recommend good sniping games? Options

[Wounded Ronin]

I was wondering if any of the gamers here could recommend good sniping games to me. What I'd be looking for in a sniping game is more realism; I would like to be able to adjust scopes for range and have the gameplay be slower-paced and demanding of more careful stealth.

I've already played some games that sort of fit this bill but IMO none of them fit it ideally. I've played:

Line of Sight: Vietnam - this is a really fun sniping game set in the Vietnam War. The game pace is slower and stealth is key as taking a shot when enemies can detect your position usually results in them circling behind you and killing you. However, it's not terribly difficult to make the shots and although you can adjust zoom on your scope you can't adjust for range.

Delta Force: Black Hawk Down - this is the only FPS game I've played that actually lets you adjust not only the zoom on your scope but also adjust for range. It's possible to aim your crosshairs higher or lower than the target appears to make your shot depending on the distance of the target and the range you've sighted your scope in for. However, in practice you never use this feature in this game since most of the combat is at relatively close range and it ends up being more like a typical semi-realistic FPS where you end up spraying autofire with your carbine and sprinting to cover. There appears to be no accuracy penalty for walking and shooting at the same time.

America's Army - I really loved the sniper qualification range where you had to go prone, deploy a bipod, and fire when fully exhaled to hit the white target silhouette way out on the range. However, in practice, you never end up making these kinds of trick shots in multiplayer because basically things take place at much closer range.

I suppose that there might not actually be games like what I'm looking for. I suppose that the nature of most FPS engines is that there's a limit to how far away you can have enemies be without hitting system limitations.