.30 Carbine S&W
The thread about 9mm revovlers reminded me of the WW II experiment with the .30 Carbine round. Seems the Army was considering a .30 Carbine revovler to supplement the M1 Carbine. (Wasn't the .30 Carbine designed to replace the pistol as a sidearm?)
So far as I know, Smith & Wesson built one specimen in .30 Carbine, sort of a reworked M1917 revovler. The gun used half moon clips a la the .45 caliber version.
From what I gathered, the blast and flash was just too much for the average soldier of the time, so the project got no farther. But, interesting anyway.