The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 5: Forts and Artillery.
Francis Trevelyan Miller, Ed.

the introduction of breech-loaders for the military service throughout was now very generally recommended. The success of the Spencer, the Sharp, and some other types of repeaters had brought them prominently to notice. The great objections to the breech-loading small arm, in addition to that heretofore mentioned, were that these pieces were heavier than the muzzle-loaders, did not shoot as accurately, were more expensive, and more liable to get out of repair. Besides, dampness penetrated between the barrel and the breech; there was greater risk of bursting; the cartridges were troublesome to make and expensive to buy; the ammunition was heavier, and the projecting pin of the cartridge, then thought a necessity, was liable to cause an explosion by being accidentally struck.

when the War closed, the activities of the Ordnance Department were at their height. Forty-three million one hundred and twelve thousand dollars were spent during the last year, and the main efforts were directed toward providing the same types of materiel that had theretofore been supplied. The manufacture of arms at the national armories was reduced as rapidly as consistent with the economic interests of the Government. With a view to changing the old muzzle-loaders to breech-loaders, extensive experiments were made, but had not, by that time, produced any satisfactory results. The Secretary of War recognized that the importance of the matter demanded that time be taken in reaching a decision, and insisted that no model which had defects of well-known character be accepted. The Department had permitted about five thousand of the Springfields to be altered to suit a plan tentatively adopted, and these rifles were issued to troops, but at the time of the cessation of hostilities these were still undergoing tests, and the plan had not been found satisfactory.

there were one million Springfields on hand in the armories, and about one-half million captured muskets of domestic