The only trust worthy safety is an open action. Control where the muzzle is pointed and double or triple all safety procedures and everything should be fine. I store with no ammunition in the firearm, the rest is academic.
That is EXACTLY how a weapon is turned in to the arms room, open chamber, bolt locked to the rear, handed to the armorer butt first.
The armorer then drops the BCG and hammer after verifying a clear chamber, closing the ejection port cover, NO MAGAZINE, leaving selector in SEMI and then placing the rifle in the M12 rack.
Safe and proper storage.
