However, firearm silencers are illegal under Federal Law, therefore even if the state of Washington actually does repeal their law on firearm silencers, then you will still have to contend with the Federal Law on firearm silencers.
Sorry, but I really think that you need to research the procedural aspects of this issue a bit more.
This is the kind of woo that I am very sorry to see on this website. You have no good reason to actually believe something is true, but you claim it anyway. Why not post a link to the federal law that says what you claim? You won't because there is no such law. There may be some people on this website stupid enough to believe what you claim, but I am not one of them. I am certainly not stupid enough to post a video of myself breaking the law.
I make silencers without a license as a hobby. The feds only require a license if a person makes a silencer as a business. They do not require it if they are made for personal use. The process is simple. I download the ATF form 1 from the ATF website here; http://www.atf.gov/forms/firearms/ . I fill it out and sent it in along with a check for $200. Since I use a trust to own the silencer for me, so I do not need to send in form 5330.20, finger prints or my photos.
ATF approval is a routine matter and I have never heard of anyone being denied authorization to make a silencer as long as they filled the forms out correctly. The simple fact is that I do not need a federal license to own, buy, make, sell or use a silencer in the USA.
What I do need is to live in one of the 37 states that allow civilians to own a silencer. I also need to get WA State law changed before I can use one here. The WA RCW's prohibit all silencer use; they do not make exceptions for anyone, police and military included. I have heard that the police routinely use them, but they are not prosecuted even though the AG claims there is no exemption for the police.
If there were fewer fools in Olympia that behave like you, then I think I could have gotten the law changed years ago. I have to deal with this crap often and it gets old at times. But in 13 years I retire and will leave WA for good and not have to deal with the idiots in Olympia anymore.
Ranb