1858 New Army Conversion, Blue Steel Frame and Backstrap, Brass Ttrigger Guard The Remington 1858 New Army Conversion was among the first of the Civil War percussion era revolvers converted to fire metallic cartridges. > The original cap-and-ball cylinder was altered or replaced by a cartridge cylinder. > A new breech face with a loading gate was added. > The frames were dovetailed to permit the insertion of an ejector assembly. The earliest model, introduced by Remington in 1868, chambered 5 .46-caliber rimfire cartridges. Later, 6-shot versions were chambered for .44-caliber centerfire rounds. Today, this Remington is offered in a 6-shot, .45 Colt configuration.