Consider the 22 magnum. No case neck. The case expands in the chamber, causing a seal. A higher pressure cartridge such as the 17hmr will seal better. I had an old Remington 22 that would not seal with subsonic ammo and would spit back through the cocking knob. With regular and up ammo it was, and is, fine. The recalls involved auto loaders due to the round being pulled back in the chamber before the pressure was down, causing issues. Lefty's shooting 17 auto loaders beware.
