I have to agree that a .22lr revolver would be a good firearm to learn on.
One problem that some have with the revolver is that they like to put the non-dominant hand thumb behind the hammer, then when they transition to semi-auto, the thumb automatically goes behind the slide.
Grip the revolver the same as a semi-auto (with both thumbs along side), cock it with the non-dominant hand thumb for single action. you should not have any problem.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
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