The inside baseball on this is that the Republicans put 120 proposed amendments on it to delay its passage.
https://app.leg.wa.gov/billsummary?B...4&ceid=3251341
"We are outraged by this blatant attempt to misuse procedural measures to run out the clock on this lifesaving policy,” Renee Hopkins, the gun safety group’s CEO, said in a statement moments after it became clear the bill would die. “In Washington state, at least 26 people have been killed and 45 more have been injured in mass shootings involving high-capacity magazines, including the shooting in downtown Seattle just last month that left one dead and seven others wounded.
https://mynorthwest.com/1727463/gun-...gets-new-life/
(Yep, the gun safety group is referring to the Seattle gang shooting between felons, which killed and injured innocent people....)