What caliber could it be?
My brother has a J.Stevens & Co. pocket rifle that has a patent date of Sept. 6, 1864. It has an 18" smooth bore barrel and a metal screw on stock and a pistol grip. It was made after 1864 but before 1886 when the company name was changed. The problem we have is we don't know what caliber it is. A 44 cartridge is to small and a 45 is to large. What could it be? What is a 44-40?