This is lot #646 in the upcoming RIA Premier Auction. It was scheduled for April, but has been postponed – check their web site for upcoming Online Only auctions every month, though!
The pistol colloquially known to American collectors as the “Papa” Number is actually the Modified Nambu Automatic Pistol Type A – an improvement to Kijiro Nambu’s original design (the “Grandpa” Nambu). The Papa was introduced at the Tokyo Artillery Arsenal in 1906, continuing the same serial number range as the Grandpa. It would remain in production there until 1923 with 4600 made, and was also manufactured by Tokyo Gas & Electric from 1909 until 1928 (with an additional 5700 made).
Although marked “Army Type”, the Papa was never formally adopted by the Japanese Army. The Navy did adopt it in 1909 however, and Army officers purchased them as well, as they were required to supply their own sidearms.
The Papa differs from the Grandpa in a number of areas, although the basic mechanics of both pistols are the same. The Papa has a larger trigger guard, swiveling lanyard loop, no stock slot, and a redesigned magazine with an aluminum baseplate. Magazines are not interchangeable between the two models. Production of the Papa ended at the Tokyo Arsenal basically because of the 1934 Tokyo earthquake, and it ended at TG&E after the Army adopted the Type 14 in 1925 and the Navy followed suit in 1927.