*Sigh*
Walked away from a .30 Carbine BH last year. Good price, too.
Having read various reviews of various pistols in .30 Carbine, I figured the thing would never get to the range, and if I tried to use it in the "heat of the moment" it would wreck my hearing.
Talked with a couple of gunsmiths about it, including my current smith (who loves M1 Carbines). Consensus seems to be that, given the size and shape of the cartridge, and that it looks like a pistol cartridge, some companies just had to try making a pistol for it.
It's not a pistol cartridge, despite its looking like a cross between a 9mm and a .357, only skinnier. The load "expects" to be fired from a long barrel and, when fired from a short barrel, the powder -- lots of it -- is still burning as the bullet exits the muzzle.
Daylight-visible fireball. Sonic concussion.
Guess when I get my Blackhawk, it'll be a .357 mag.