LeMat originally chambered his pistol for .40 (or .42) caliber revolver bullets, with a .60 (20 gauge) smooth-bore barrel, and had a jointed ramrod (mounted on the right-hand side of the frame), which was used to load both barrels. Later, during the American Civil War, a lighter .35-caliber pistol with a .55 caliber (28-gauge) smooth bore barrel was produced, but as these were non-standard ammunition sizes (.36 or .44 caliber were most common for contemporary revolvers) LeMat owners had to cast their own bullets (as opposed to being issued them from general military stores). The final models of the LeMat were produced in .36 or .44 caliber in response to these criticisms, but too few of them managed to get past the Union blockade of the South during the Civil War to be of any real use.