.22 LR semi-automatics like the Ruger Mark I/II or III are very popular for taking the concealed carry class in OK. The extremely short distance involved in the qualifying course and the fact that it is simply a safety/gun handling course means that you're not really going to get any meaningful practice in. The qualification requirements are such that...
1) if you qualify with a derringer; you can only carry a derringer
2) if you qualify with a revolver; you can only carry a revolver or
3) if you qualify with a semi-automatic; you can carry any handgun that is legal for concealed carry.

Soooo a cheap to shoot, semi-auto .22 LR is frequently used.
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