I'm not taking anything away from the story or the citizen involved, but I suspect there's a bit of Texas-sized exaggeration involved.
Under optimum conditions, firing a 44 magnum JHP from a rifle with optimum muzzle velocity, you're looking at something in the neighborhood of 6 to 8 inches of bullet drop by 100 yards. Past that, I don't know, but at a rough guess, I'd think he'd have to be holding something like 12 inches high at the range he was claiming to be hitting at.
I also wonder what his backstop was for any misses. Another trailer? Hey, it all worked out, bad guy dead, I'm OK with this. Just sayin'...