The Nicolas Pieper Pistols
U.S. Patent 1427413 - Patent Drawing
The upper drawing shows a gun with the recoil spring above the barrel, but the lower drawing shows one with the recoil spring above the bolt.
Traditional darkroom photography and historical photographic processes
U.S. Patent 1427413 - Patent Drawing
The upper drawing shows a gun with the recoil spring above the barrel, but the lower drawing shows one with the recoil spring above the bolt.