[Urbane Guerrilla]

Mostly good advice there, Ruminator -- welcome to the Cellar, btw!

But allow me to insert a few modifications, for instance about handguns jamming. Semiauto designs more recent than say circa 1911 are a lot better about reliability, because basically they've had nine decades of experience now in arranging semiauto actions to make jams less likely.

It is possible, though not at all easy, to jam a revolver.

With a semiauto, jamming can usually be cleared immediately, like about a second, without tools. Some designs are not prone to the stoppages others may suffer, such as the 1911-type "stovepipe jam," which you clear by swiping the stuck, vertical standing cartridge case out of the ejection port with the heel of your left hand. Jack the slide and you're ready for battle again. Most semiauto jams get cured by "tap/rack/bang" drill. If the slide didn't go into battery -- not all the way in -- bump it with the heel of your hand. If it won't go, grab the slide and rack it back, ejecting the cartridge it didn't feed, and let it run forward again to pick up the next. Unless something's very wrong, it'll feed this cartridge the way it's supposed to, and you can go bang bang again.

A bad primer isn't a jam, but is alarming in time of trouble. Cure is still the same: rack the slide to eject the offender, and chamber the next round. The work of a mere moment.

Jam a revolver, though, and you've probably got something so messed up it's going to take some time on a workbench with armorers' tools to sort things out. You'll likely have to take the gun apart to get at what's wrong, like something down in the lockwork that revolves the cylinder and actuates the hammer.

Modern semiautos like the Glock operate so simply it's like picking up a double-action revolver anyway, and Glocks and similar actions (Smith & Wesson makes one) benefit from those nine decades of experience and are designed very jam resistant from the start.

It is also easier to shoot a semiauto rapidly and accurately. Revolvers necessarily put their chamber up high, so there's a lot of leverage when you touch a round off and it cranks the piece around in your hand. This effect is marked with large magnums, unless these have a very long and heavy barrel fitted -- the difference in behavior between an 8" barrel and a 10" silhouette shooting barrel on a .44 Mag is very great. The first bucks up on you, the second backs into the web of your hand and spanks it. Semiautos keep their barrel line lower to your hand, all the workings of the system are automatically powered and run backwards and forwards, so this kind of pistol is more ergonomic to shoot. It's a better fighting tool, overall. This is why semiauto pistols proliferate as they do -- more firepower, which has been true from very early on (8 for the 1911, 13 for the Browning HP 9mm, designed between the wars; now see 1911 actions with double stack magazines of 14 rounds in .45 and cut-down versions of the same pistol with 10, and 17 rounds of 9mm in a full-size Glock, or 19 with magazine extension buttplates, a little more bang with a little more bulk), more repeat-shot accuracy -- hits win better than misses, which is what a responsible gun owner seriously needs.

Police departments have pretty much universally converted to autoloading pistols. Weapon development tends toward the conservative, and police departments are particularly so. They are not going to take up a firearm that is only iffy. They have discovered it is important to shoot better than they used to be satisfied with, and this instrument does the job.