Re: UltraSonic Cleaners
I have used them to clean everything you said (& triggers, bolt bodies, etc) and what they work great on is dislodging minute particles, grime and grease. If want to use it for baked on carbon or primer residue, well the results were less than then expected. It did not work well for me and I would let them "dwell" in the unit up to 4 hrs. In my past life its purpose was for cleaning fuel nozzles and very fine fuel filters..
Would I spend the money on one, No. But if I had one to use, I would use it...