Magazine is for a post WW2 Walther.380, PP or PPK. As i am in the process of buying a post-war Walther. Serial Number Caliber Slide Legend Date Date Location Commercial (E/N)? 001xxx 9x19mm P38 5/57 Slide No 016xx圎 9x19mm P38 62 Frame Yes 165xxx 9x19mm P38 2/ 62 Slide No. Post-war P38 serial number versus date production chart This information is taken only from original, serial number matching pistols. It is a standard PP, there are no markings on it except for the. Pistols are not my strong point, so I need help dating this pistol. Walther Ppk Serial Number Year Chart Interarms Ppk Date Of Manufacture Greetings.I have a Walther PP for sale, and I have a guy who wants to buy it, but he won't buy it unless I can prove that it is war time. The front gripstrap is stamped '1', and the serial number 750007 is engraved in slide holdopen latch well. Experimental Walther 'Police model' pistol which served as a prototype for PP note that it has Its unique magazine has a prototype metal extension at base.