A popular gun trope in Hollywood is the old pillow-as-an-improvised-suppressor gag to produce an instant “silencer.” How legit is that?
To test, the VSO Gun Channel runs a brand new pillow to see if they can get it “movie quiet” when it comes to suppressing the sound of a few random firearms.
As far as the test goes, while VSO’s is new, the medium has been used in the past a few times already. Since you came this far, check out Jerry Miculek and Edwin Sarkissian drilling down (get it?) for reference, with varying results.