Some Colt revolvers were made/chamber for the .22 Hornet cartridge, slight taper wasn't problem just like similar shape of 32-20 cartridge also chambered in single action, few double action revolvers. Occassionaly a .22 hornet revolver will show up at gunshow, be listed on Gunboker.com. Single shot pistols with break barrel action like Thompson Center or solid framed dropping block, rolling block have been made in 22 Hornet since the cartridge is of good design for single shot use with rim, taper for ease of loading and extraction. 5.7 FN is a .23 caliber center fire in self loading pistol, not cheap though. High standard made .22 mag pistol- rimfire, not center fire. South American, maybe Mexico market has/had legal restrictions on larger centerfire cartridge pistols for civilians but allowed .22, some .25 pistols, some .32 for civilian use- body guards for some politicians and wealthy non political targets. what would have been .38 special chambering in USA would be .22 Hornet in some markets, 32-20 in some other markets or .32 S&W, 32 H&R Mag. S&W model 10 with 6 inch barrel in 22 Hornet or maybe Ruger single actions converted was noted as Mexican civilian registry on Gunbroker or other Texas dealer listing couple years back. .