Yesterday a student asked a common question -- how much gun is necessary for self-defense? We often get this question from new students and usually respond with variants of the time-honored guidance: "Use the most powerful caliber that you can competently shoot." including the fact that "For Personal Protection classes, the NRA recommends at least .38 Special for revolvers and 9mm for semi-automatic pistols.
Today the student followed up with further questions as she was a petite female concerned with carrying a concealed firearm. She asked whether the modern compact .380ACP handguns were realistic choices. We then discussed the various considerations that impact your defensive carry gun and its caliber: Ammunition has progressed a looong way since John Browning developed the 230 grain hardball .45ACP. And the compact gun that you are actually carrying on your body has great advantages over the full-size gun that you left at home because it was too large to effectively conceal. Also, sheer knock-down power is but one aspect of effectiveness -- marksmanship and shot placement are critical elements of defensive shooting. The big gun that you miss with is less useful than the smaller gun that you are very capable of shooting well.
The linked article below takes this discussion to further depths and illustrates the EXTREME case of .22LR for personal defense. We do not recommend the 22LR as a primary choice for a defensive firearm but the discussion in this article does illustrate the many complex factors to be considered. For those having difficulty in competently shooting larger calibers, we have ALWAYS been able to train them to use the larger calibers with competence and confidence. We carry a wide range of high-quality defensive firearms -- all the way up to the Desert Eagle in .50AE, although that also is unlikely to be a good choice for a concealed pistol unless you are Paul Bunyan.