A gun shop and indoor range (Rifle Gear in Dallas, TX) recommended this stuff:
SchlecTek Suppressor Cleaning Solution. The website says, "SchleTek Suppressor Cleaner Evolution is environmentally friendly, water soluble, and has been positively tested for compatibility of materials. Due to its special pH-neutral formula it does not harm any surfaces and is suitable for all materials and coatings, including Cerakote™." They also state their solution can also be used in ultrasonic cleaners.
The gun shop rents machine guns and suppressors, and their gunsmith uses it extensively. The sales guy said it was like magic in a bottle, for cleaning suppressors, but cautioned that it stinks to high heaven.
I bought a bottle, and I can confirm the foul smell. I haven't had a chance to try it yet, though. I need to pick a nice day and leave it outside to soak.
