The Cascades start just east of you ! Been up to Leavenworth (considered moving there) and the local Sheriff up there laughed when we asked where we can shoot. "Just not in m direction!" Pretty much anywhere that's marked (I believe its) green on a forestry map.
Check out your local law enforcement and ask about good locations in the hills near you. They'll be happy to tell you where good spots are.
Remember - pick a good backstop, avoid steel core/AP/mixed metal bullet casings (attracts a magnet) so you don't spark a fire, and food/water. (that's "Garand food"

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