DB Foam was introduced at SHOT show 2017 by Inland Manufacturing. The foam is designed to be sprayed into your room temperature silencer to displace the oxygen, eliminating first round pop, and adding an average of three to five decibels of suppression to your silencer from a ten round string. DB Foam is water soluble but as it dissipates during shooting, it actually provides a bit of lubrication and acts as a mild cleaning agent. So, it is safe to use and store in your silencer.
My process was to create a baseline using my own sound meter and firearms I have shot and reviewed, along with silencers I have reviewed. I shot three rounds and got the average decibel rating, then foamed the can and repeated the process. Note, my db meter measures the entire soundwave not peak sound, so what that means to you is what my meter is reporting is about what the average human ear hears.
The firearms and silencers I used, with hyper links to the reviews, were
You can see how the foam totally fills the baffles and dissipates oxygen.
After everything was over and done, this is what I learned, there is a learning curve to getting the silencer full of foam and not making a mess. Using the applicator, you need to start at one end and slowly fill the silencer as you move the can of foam and applicator out of the silencer. It took me a couple of tries to get the hang of it, so you may want to have a towel handy the first time you try it. With a full silencer of foam, there is noticeably more smoke generated during live fire, though this did not affect reliability. As the foam dissipates the smoke is reduced. After some thirty rounds or so, the foam is completely dissipated and would need to be reapplied to continue to benefit. It is recommended to let your silencer cool before you reapply. According to my sound meter I got an average increase of suppression of seven decibels over three to four rounds. That is on par with what the manufactures suggest you can expect. First round crack was completely eliminated with super and subsonic ammunition. In conclusion, the DB Foam from Inland did exactly as it is advertised and an inexpensive and safe way to get just a bit more suppression out of your silencer. I believe the biggest benefit is the elimination of the first round crack, which would be especially for people using a silencer for hunting and without hearing protection. Since the silencer can be stored full of foam without issue, it would make sense for people who wanted the most suppression out of their can.