It's all about money,,,
I shoot a lot of .22 because that's what I can afford to shoot the most of.
If I were a rich man I would shoot much more 9mm and .38 special.
I own several "pairs" of guns,,,
Such as my Model 15 in .38 Special,,,
And my Model 18 which is chambered for 22 LR.
The guns are identical except for the cartridge,,,
Except for the recoil factor they shoot much the same.
My typical routine (before the rimfire ammo shortage) was 50 rounds of rimfire,,,
Followed by one or two cylinders of centerfire ammo,,,
Repeat as often as desired.
There is no definitive answer to your question,,,
I feel that shooting a lot (even with the measly rimfire cartridge),,,
Has mad me a better shot than if I would have shot the same money in centerfire only.
Other people say that you should only practice with your main caliber,,,
They believe the recoil is very important for consistency,,,
I don't think either side can claim to be "right".
Can you afford for her to practice enough with a .380,,,
So that she has confidence in her abilities?
If so there isn't a problem,,,
Wear that .380 out.
If cash is limited,,,
You might consider a .22 for her.
Make your decision on what you think is feasible,,,
Not what we Internet experts say.
Aarond
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