About 3 years ago, on a friend's rural private range...
I was going out to the range to meet my father. The range is really just a natural berm created by some erosion. I drove my pickup around the edge of the berm and saw my father reloading his Browning High-Power .40 near the target stands. He saw me, and smiled with a slight wave with his off hand, the Hi-Power still in his shooting hand.
About this time, Dad noticed the rather odd expression on the faces of me and my friend, also in the pickup. We were noticing a giant, um? What the heck is that thing?-- stalking up on my father from behind. The range is set in rural cow pasture, and there were no fences for a few hundred yards. The bird had simply come from over the horizon. It had its head down low, and was approaching my dad from the rear.
Just as it got within about 10 feet of my father, its motion managed to catch my father's peripheral vision. He spun around, .40 at the ready, and stopped. This will be one of those tableaus burned in my mind that I will take with me to my grave. Of course, it's blurred somewhat by the tears that were streaming from my eyes, I was laughing so hard.
The emu took off, recognizing that it was outgunned. It did a stalk around us in a semi-circle about 150 yds in radius.
Dad got on the phone with the landowner, who expressed his astonishment that the bird had not yet been eaten by the local coyote population. He'd seen the bird for the first time about 2 wks prior, when it had just wondered on property, from an escaped flock of them of a raiser who had gone bust. Dad asked if he wanted to keep the bird, and he said "Good lord, why? You want it?"
At about this point, I popped it from about 150 yds with a 100g .257 Rbt Nosler Ballistic Tip, down-loaded to about 2600 fps. Shot hit the spine just behind the point where the neck reached the body. Bird went down, and a cloud of dust went up from the tall grass where it fell. We went up there and found a rather frightful scene of the serpentine head flailing around and the legs tearing up the dirt as the bird's body came to accept that it was dead. Think of what a chicken does when its neck is wrung, but apply it to an 80 lb 5 ft tall bird. We didn't get close for 3 or 4 minutes.
The meat turned out to be surprisingly good and red. We also found it to be pretty moist, actually. Closest thing I could compare it to would have to be beef. Go figure. Also surprising: NO breast meat. NONE. All the meat on the emu came from the legs and the "oysters" area, the counter-balanced rear side of the bird. We made lots and lots of good jerky, and smoked the drumsticks, which went roughly 5 lbs ea, and about 2 feet long.
The only dangerous part of the bird is the legs, which have amazing 4-toed (three in front, one in back) clawed feet. I can see why this bird had no trouble with coyotes; it could likely kill one. But I don't think that any heavy armament would be necessary. Heavy 7.5 shot bird loads aimed at the head or the joint of the neck and the body would work great. If you shoot one with a rifle, pop it in the high front of the body, where the lungs are. The lungs are surprisingly small when empty, but perhaps they're bigger when the bird breathes in. The diaphram is pretty high in the chest, too, though. As I say, there's no breast meat, so you don't have to worry about spoiling it with a body shot like you would a turkey. Just keep your shot forward of the the legs and above the thighs. I personally think that these would be great handgun game. I almost got to see what a magazine full of .40 FMJ's would do to one!