400 yards on any running game animal is like going to Vegas and trying to beat the house. Growing up we did deer drives in East River South Dakota. If you couldn't hit a running deer you didn't fill your tags. The only reason I was proficient at it is that I shot a lot of running rabbits, upland, and waterfowl. The concept is the same - start behind the target, swing through, squeeze the trigger. Is it always perfect? No. It isn't. Some of us were better at it than others. I haven't shot at a running deer in around a decade, as all my hunting is now done from a ground blind with a single shot pistol and a rest, though I can say that I've killed three deer on the run with a single shot pistol as well, all under 150 yards. Most of our rifle shots on running deer with rifles were under 200 yards. One of the farmers I grew up hunting with shot a Remington 760 pump in .30-06 and shot 180 gr. factory ammunition. Iron sights. Before I was old enough to hunt I was his "magazine man". As in, I'd post up with Lester and have two spare magazines loaded and ready to hand to him. That man mowed down deer and antelope at ranges from 50 feet to literally killing four antelope on the run with four shots at 350 yards. I also witnessed him shoot a pheasant rooster on the fly at 75 yards with his .30-06. But he is a severe exception. I wouldn't want him shooting at me at a half mile with his .30-06 and iron sights. If you're calling BS, go ahead. But I've witnessed it with my own two eyes. The last two deer I killed on the run were about 100 yards off, two mule deer running flat out. Two shots, both literally through the heart. Some luck? Yep. But there is a certain measure of skill involved in shooting running game. And it is only gained by doing it. Your friend hasn't done it. And 400 yards out on a moose isn't the place to start trying to learn.
