The 9x19 fires the same diameter bullet, usually heavier and faster. All 9mm guns except for the HiPoint use a locked breech to contain the higher pressures. The .380 with its lower pressures usually have a heavier slide and spring to contain the pressures. For weak hands the 9mm is usually easier to retract and has softer recoil (Beretta model 86 has a tilt up barrel). The blowback of the .380 is usually snappier.
There are a few locked breech .380 on the market now the SIG copy of the Mustang and the small Kahr. As far as determining a good weapon for your wife, how experienced is she with firearms? I feel the smaller guns require more gun knowledge experience. Same as like shooting skeet or hunting with a .410 compared to a 20 ga. I would suggest that she looks at the smaller 9s on the market first.

CD

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