As stated below, the Smith carbine was a rifled, breechloading .50 caliber weapon used primarily by Union cavalry early in the war. Some 30,000 were issued to Union troops, 7,000 of them in 1862. It was produced in the Springfield area of Massachusetts under three different company names.
A typical breechloading carbine, it was opened for loading by depressing a latch forward of the trigger to release the barrel. The barrel then pivots downward on the frame to a right angle so the ammunition may be loaded. If it helps to visualize the process, the angle was nearly twice as great as the average break open shotgun of the time. The overall length of the carbine was 42 inches, with a barrel length of nearly 22 inches. It weighed approximately 7.5 pounds.
The Smith carbine was the fourth most popular carbine used during the Civil War. It was later surpassed by the Sharps, the Spencer and the Henry. The primary reason for this is ammunition. The Smith used special ammunition housed in a tube made of india rubber. This contained the cartridge when fired and prevented flareback. The carbine could be fired using loose powder cartridges, but the resulting flareback could be hazardous to the firer’s eyes and face. Not long after the invention of the carbine, Smith & Wesson and Henry created self-contained metallic ammunition. This ammunition, unusable in the Smith led to the development of the repeating carbines that surpassed it later in the war.