I just learned that Kel Tec introduced a new pistol in .22 long rifle, that holds 33 rounds in its unique double staggered magazine. It's called the CP33, and is basically a .22lr version of their PMR30 pistol, at least in appearance.
new CP33
At 24 ounces, it's a little heavier than I'd prefer, but may still be an option as a rimfire trail gun. I'm interested in reviews on accuracy and reliability if anybody has seen one.