The cartridge on the left is one you will probably never see outside of a serious ammunition collection or gun show. It’s called a “tround” and was invented by David Dardick for his Dardick Series 1100, 1500, and 2000 double-action revolvers. Introduction was at the 1957 NRA Annual Meetings. Instead of a brass cartridge case, the tround was plastic. It had a conventional primer, powder and bullet.
The case shape permitted trounds to be stacked efficiently in a box magazine that was inserted in the pistol grip of the revolver. The trounds fed up into a “cylinder” that had V-shaped notches into which the trounds seated. Guns were available in .38 or .22 caliber and there is some argument as to whether a total of 40 or 50 of the guns were made. The public was never overwhelmed by the tround, nor the Dardick revolver. It is, frankly, an ugly-looking gun. There have, however, been successful applications of tround technology reported in hard rock drilling and military gun applications.
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