11-12-2014, 08:23 PM
When I used to do Cerakote/Duracoat for a living, I would just avoid getting too much material in the port if it was exposed (usually a gas block was already installed). This method was enough to never have a problem with .223 and AR-10s. Occasionally we'd poke a toothpick into the gas port before coating to mask it up, but I never found it to be a 100% necessary step and I was the one doing function checks on all the guns before they went back to customers. I would assume your applicator probably has a similar mindset, especially if he has to do the re assembly as well.