Entities Disappearing?

I've tried debugging but am stumped. Essentially, I have a location that I occassionally update, and when I do, I move the Entity to the same location with the setLocation(x, y, z). It works, however normally after a few ticks of spawning the entity and moving it, it stops and then disappears. Here is essentially the code:

Code:

entity = ((CraftEntity)this.location.getWorld().spawnEntity(this.location, EntityType.SNOWBALL)).getHandle();
.....
entity.setLocation(location.getX(), location.getY(), location.getZ(), 0, 0);

The code before the ... is run once to spawn it, then the code after the ... is run once every tick with a new location. It works and moves them properly usually for a few ticks, but then the entity will stop being teleported (it's still alive and setting the position), then it will disappear.

 

Try to run it not every tick, but every 5 ticks, for example. It's still 4 times/sec, so it shouldn't be a problem.