If you just want to start "shooting" with a pistol I strongly recommend a good .22 caliber. The reason is you'll be able to shoot a LOT and that builds good habits and proficiency without costing you a lot of money. That last part is no small matter. Cabelas right now has 9mm Winchester 115gr FMJ "USA" white-box on sale for 14.99 per 50. That's about as cheap as it gets for something with any brand recognition. If you only paid that much (no taxes/shipping/etc) you're still looking at .30 cents per shot. That means you load up a G19 mag with one in the pipe and by the time you empty the weapon you've spent close to $5 right there. OTOH they've got a 525 count box of Remington .22 HVHP's for 20.99, or .04 cents a shot.
One of the best things I ever did was get a .22 conversion kit for one of my Glocks. Same sight picture/grip/trigger/etc that I could practice with before shooting a few of the "real thing". (I also handload though, so even the bigger calibers aren't quite as expensive)
Modern bullets have done much to increase the effectiveness of the 9mm but the .40 does more of the same and can now be had in platforms as small as most of the 9mm's. A 9mm beats the crap out of having to defend yourself with harsh language or a stick but unless I'm going for a real micro-pistol (and then you might be better served with a .380, which in actuality is just a 9mm "short") I prefer the .40.
One of the best things I ever did was get a .22 conversion kit for one of my Glocks. Same sight picture/grip/trigger/etc that I could practice with before shooting a few of the "real thing". (I also handload though, so even the bigger calibers aren't quite as expensive)
Modern bullets have done much to increase the effectiveness of the 9mm but the .40 does more of the same and can now be had in platforms as small as most of the 9mm's. A 9mm beats the crap out of having to defend yourself with harsh language or a stick but unless I'm going for a real micro-pistol (and then you might be better served with a .380, which in actuality is just a 9mm "short") I prefer the .40.
