I have found information on several websites describing Spanish proof marks as consisting of single/double alphabetic characters that may include a number (1 or 2) identifying dates of manufacture from 1927 (A) to 2006 (Z2). 45 ACP that I acquired back in 1978/79 that I am trying to determine the date of manufacture. I have a Llama IX-A (SN 45xxxx) chambered in. I'm not talking about the four legged model.
