It's a deliberate attrition strategy. "Sure, you can keep the guns you have for now... have fun shooting 'em when you can't get replacements for wear parts." Much like they wanted to do with closing the Federal MG registry in '86 but missed the mark...My understanding of WA law is you can't sell any parts needed to operate an 'assault rifle' properly or a scary part. The trigger. hammer and buffer should have been banned.
Its a stupid law. Without the buffer, gas block & tube, the AR becomes a single shot and doesn't fall under the definition of 'assault rifle'. Only the banned list prevents selling those parts. They should have banned drilling gas ports on the barrel and when its overturned, easily converted.