I am posting here because I see other threads about Browning and FN. If you look at the photos of this Browning 1955 on Gunbroker, specifically the photos that show the part of the barrel that is visible inside the ejection port, you see stamped characters that appear to read "9m/m00". Certainly the 9m/m means 9 millimeter, but what is the meaning of the double zero? The gun is probably a 380 ACP, which could also be stated as 9m/m Short, 9m/m Browning, 9m/m Kurz, 9m/m Corto, etc. But that 00 has me curious.
BROWNING MODEL 1955 9MM/.380 SEMI-AUTO PISTOL NR : Semi Auto Pistols at GunBroker.com