I think there have been many good subjections. I would shoot the 22 to get in some cheap practice. You should do a bunch of dry firing with your double (use snap caps) This will help you to build your strength and endurance. You can set up a target in your house and practice bringing the rifle up and being on target, Holding the rifle brings familiarity and helps confidence. Dry firing is a great practice used by completive shooters for years. You can even practice reloading (using snap caps).
Bill