heres something i noticed from the video: the shooter had to clear at least 3 malfunctions due to police finding 3 unfired 9mm rounds. when using a silencer on a hot round like a 9mm, you need to use subsonic ammo for it to be effective. subsonic ammo often does not provide enough back pressure to cycle a semi automatic weapon, hence the shooter having to pull back on the slide after each shot, ejecting unspent rounds. it doesnt look like the shooter was prepared for that, which leads me to believe that someone gave him the weapon and he did not have experience with it.  9mm is a light and fast round that produces a sonic crack that a silencer does not compensate for. hence the need for slower (subsonic) ammo. .45 is much better for a silencer due to the heavy weight of the slug (providing back pressure) and the slower speed of it (no sonic crack).  just some thoughts.
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