Nice Ruger. I had one a while back. I really don't see why you need another magazine. That won't stop a bear and it's doubtful you would see the cougar/mountain lion until it's too late to shoot.Maybe you meant the one included in the weapon, if so,sorry. Maybe sub out the flashlight for a head lamp, like backpackers use or better yet a light system that mounts to your handlebars. The water is your biggest weight and in the desert I see little chance of riding with less. Just make sure you are not overpacking. If you must have a large "what if" overage of water, food and clothing think about the previous posters idea of a rack. Dropping the roscoe would offer the most weight savings aside from the agua. Are you absolutely POSITIVE you need it?