G, barrels weren't boiled at 130 or 180 degrees. Water boils at 212 degrees F.

After rusting, barrels go into boiling water for 5-6 minutes, come out and then card with a gray scotch brite pad then go into etching solution for 5 seconds. Immediately after dipping in etchant come out and go under running water using scotch brite pad again.
Repeat process until satisfied. So far I have never neutralized with baking soda.

David