I think a lot of people choose .40 over 9mm because 9 is a higher velocity, smaller diameter bullet and so has a somewhat higher probability of leaving the intended target and hitting something behind them. But as mentioned, using good quality defensive ammo (JHP), this should reduce the possibility - at least in my mind.
I intend to purchase a 9 for my next carry weapon because the target ammo is so cheap. I love to shoot my .45 1911 - LOVE IT!!!
But it is just too expensive. I really want to try some shooting matches - so I really need to have a gun that cost less each time I pull the bang switch.
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