Guns in .22LR are your friends.
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Centerfire is a little more 'real gun' than a .22.
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9mm Carbine. ... Much safer (as in muzzle awareness).
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Introducing or re-introducing people to shooting, help them learn form and fun before they also have to deal with recoil. My .22's are just as much real guns as my 1911 .45ACP!
I will agree that a carbine is a good idea for first timers. Yes, long gun does enhance muzzle awareness. Start out with prone position or seated with table and support, not standing.
Even with handguns, seated with support is anice way to get started.
For the ladies, assuming there will be semi-automatic guns used, close, high neck shirt or blouse, preferably turtle neck or mock turtle neck is an important aspect. Open, gapping, necklines look nice at the dance club, but seem to be a magnetic basket for hot brass. Talk about ruining the fun!
If you have the time and the shop a has the guns available, I'd start with a bolt action .22LR rifle, move to a .22Lr revolver, like a s Single Six, then finish off with a .22 semi-auto pistol.
An advantage of a bolt action rifle and a single action revolver is that the process forces a slower shot to shot change. This will increase accuracy and focus.