Even shooting them at steelies at short range (10yds), you can see most of them after they hit, they continue to burn in the dirt wherever they land, usually nearby.
7.62 NATO, tracer burnout is around 900m give or take, 5.56 is pretty close to that although don't recall the exact distance. I know it's at least 800m from shooting that distance with mags full of tracer rounds. They do spark up pretty quick after leaving the gun.