The ejection could do with randomising as Theaps suggests, but it also doesn't really look like an AK ejecting, depending on how nerdy you want to be about it.

AK's were originally designed to fire steel cased ammunition and have a very high bolt carrier to bolt mass ratio - case heads are thrust onto the receiver cover which pushes the case forwards - this was initally done to ensure that the cases did not fly back into the face of the firer, but the net effect is, if you see an AK ejecting, the cases will appear to fly forward slightly not directly sideways.

In terms of cases flying all over the place, you don't get a lot of random direction ejection in Russian made AKs although it is common in other Eastern Bloc and Chinese copies due to differences in the quality of materials used in bolts and carriers. The original AK's were given rather more weighty bolts and carriers to cope with excessive heat at ejection. I have seen both sorts fired at fairly close range (although when people fired them at me I took very little notice of ejection patterns I am afraid), and there is a discernable difference in pattern as well as a slight one in sound. Watch film of Afghani troops firing their cheaper imports and compare with Russian Army to see the difference.

The effects you see in movie films usually come from modified bolt carriers firing blank ammunition - how it looks in the movies is good for a movie effect of course if that is what you are after.

The ejection pattern also varies with the use of brass cases, as they are usually damaged by ejection and come out with a visible dent at slihtly odd angles to each other. If the ammunition you are showing is military type the cases will usually fly less far than civilian type as well.