You're right, coldbeer, the .30 carbine cartridge is not really a pistol round, it was indeed designed for the carbine from the outset. The actual ballistics though, are equivalent to magnum handgun loads, and there are a couple of handguns chambered for it. Out of the carbine, you get a gentle shooter that's a ton of fun to shoot; as noted earlier, it's a dandy close-range defensive rifle, especially with expanding ammo. It is actually the first 'Personal Defensive Weapon'.
For your entertainment;
http://en.wikipedia.org/wiki/M1_carbine