I've grown autos for a couple harvests. Yield was all over the place but I used the same exact setup for each plant, all of them being Auto AK47.
One plant I yielded 3/8 Oz of rock hard, crystalline nugs. Another plant yielded over 3 Oz of huge, fluffy sativa bud. On average though, an ounce sure sounds about right.
I have stopped growing auto's, though. I don't like having to constantly stay at 18/6 or 20/4 and the plants that did get big also took much longer to finish, defeating the purpose of growing them. On top of that, they never really got that 'dank' smell to them. Potent, kind of, but never really smelled like weed.
Here is an account of the big yielding one I spoke of:
https://www.rollitup.org/seed-strain-reviews/183765-auto-ak47-large-phenotype.html