I tried that my first one too. I'm thinking about polishing the air flow channels to see if smoothing out the airflow quiets it down. I almost don't hate it.
I think you've got it on quieting it down my friend. Get those chamfers in there and it should do the trick, just like chamferring the air hole on a KF does. This would apply to the clone as well as the authentic.
Ok, I definitely took more than 4 seconds to fill it. Guess I need to be faster. I was trying to gentle with pressure. Using a needle bottle (Nicoticket). Should I use a syringe? I keep getting a few drops out the airholes.
I fill all of my ErlKs without any leaking and without an afc ring installed. Don't rush it and yet do it quickly, if that makes sense.
The easiest way to quiet the atty is to remove the airflow control ring, slip an o-ring over the 510 and snug it all the way up, then reinstall the airflow control ring.
And what about those of us that don't use the afc ring at all? Hmm?
I think KTMRider is onto something with his polishing line of thought in that regard.