Those two spots, equidistance from the center of the picture, about halfway to the horizon are the steel buffaloes, life-sized. 800 yards away. Thats not quite half a mile, for those keeping score. They are easy to see in this picture, since they were just painted.
After an hour or two, the targets get to be a uniform gray-color and it is hard to see hits, even with a powerful spotting scope. So, periodically the rangemaster will stop the line to "paint the targets", which is exactly what it sounds like. Anyone shooting gets to finish their string of shots, then everyone moves back across the dirt path, well behind the firing line. No guns are left on the line during painting. When the line is safe and secured, a team of painters zooms out on four-wheelers armed with cases of quick-dry spray paint to touch up the targets. The lead splatters all get covered up and a white dot is added in the middle, to help the many aging eyes in the audience to get their bearings. When the painting team gets back safe and sound, the line starts up again where it left off.