...is the ultrasonic cleaner. I've experimented with different cleaning solutions from water with dawn, to Pine Sol and water, to Simple Green Extreme (the aviation/aluminum-safe stuff) w/ water and found that while Pine Sol and water does really really well on suppressor baffle carbon/buildup - it can/will strip the black oxide finish from nitrided steel. It also dulls anodized aluminum a tad, and seems to turn 17-4 Stainless either clear (like shiny bare metal) or yellow. And this was just with the cheap jewelry ultrasonic from Amazon.

The Simple Green Extreme hasn't removed any black oxide finishes from steel, even when I left my parts in there for about an hour. Water and dawn isn't able to touch anything serious - it never worked that well in the ultrasonic. Heck it didn't even get my apple watch band all that clean.

I decided to upgrade to a 2.0L ultrasonic (the one with the rotary knob for timer and heat) because I hated having to constantly turn on the cheap jewelry ultrasonic every 3 minutes (for total of 30 minutes). I've never had to use the heating option. Just 15-30 minutes seems to do the trick. The 2.0L tank vibrates a lot stronger than the cheaper jewelry cleaner.

I place my parts inside a freezer bag / zip-loc with the cleaning solution, and then fill the ultrasonic tank with water and have the bags floating in there. I learned this from others on Reddit.

Pistol barrels seemed to clean real well - except for copper splatter/deposits. The S&W M&P 5.7 is a gas operated pistol and the copper splatter at the gas port still requires scrubbing with a SS brush. But otherwise carbon just flakes right off. I threw in an old Q Cherry Bomb muzzle adapter and saw carbon literally flake off the tiny ports and insides.

But the real test was the AR15 BCG and bolt. I always hated scrubbing the inside of the BCG and the tail of the bolt. While my SA AGB in vent mode (just 24 clicks total or 6 clicks past full open) reduces the build up on the tail significantly, it still requires some scrubbing usually. The ultrasonic basically allowed me to wipe all the carbon that didn't flake off. There's no buildup inside of the BCG. I just used a Q-Tip to gently wipe the insides and it was sparkling clean.

Since I shoot suppressed, the bolt usually gets fairly grungy as does my PRI gasbuster latch. So I threw everything in the ultrasonic and they come out like brand spanking new (minus some finish wear from just normal usage). I haven't had any issues with aluminum eroding from the ultrasonic, but I also do not use the heating option as I never found that I needed it. I have cleaned aluminum baffles from my Banish 45 several times in the ultrasonic and have not observed any erosion.

I plan to throw in the Ventum 762 titanium core in there when the time is ready to clean it. The titanium baffles from the OCL Titanium have cleaned super easy with the cheap jewelry ultrasonic. And the Ventum 762 is probably my favorite rifle suppressor because of the significantly reduced blow back.

I did like the ultrasonic but I felt it required too much time.

The very best thing I ever used was the boretech eliminator all over inside and out of the bcg. It's not just for the bore. Boretech also has these polymer picks they sell that has a angled pick and a straight pick. Just perfect for the ar bcg and putting a wet patch in and just spinning it around. You can use it in conjunction with the ultrasonic where you first scrub with the boretech, let it soak for a while, then toss it in the ultrasonic to clean everything out. I just find using gunscrubber or running it under the sink for a few seconds work just as well. I had cases where I can take a clean patch, spin it in the inside of the bcg, and it would come out white still. I never seen it that clean ever before until I found boretech. I always thought you had to use an ultrasonic too.

I use Boretech C4, Copper remover, and eliminator and have been doing this for several years. They work great for the bore, about the best way to get the bore clean like-new.

For the BCG and bolt tail, they don't remove all of the stuff on the tail or the inside of the BCG. Yes I can scrape/scrub those spots clean which I used to do. The ultrasonic is much faster and easier. 15-30 minutes is all I need, and I could be doing 100 other things during this time instead of scrubbing 1 or 2 pieces. And I can throw in a bunch of other stuff in the tank at the same time, like the baffles from 1 or 2 suppressors, or pistol barrels, etc...

So you prefer to use simple green extreme? Whats your dilution ratio in the bag? I have the HB jewelry ultrasonic and do not believe it actually does anything at all.