I just picked up another Polymer compact Witness 9mm with a date coade that is very hard to read but seems to be CP. I haven't seen that referenced here. What date would that be?
Btw, I tried the magazine lookup tool, but I only have Chrome here and it just showed a blank page.
Good question. The most recent chart of Italian proof dates that I have found anywhere only goes up to 2012, when the proof code was "CI".
Looking at several of the lists of published 2-letter proof codes that start with A and then go on to B and C, we can see that the Italians didn't use every letter of the alphabet for the 2nd character. The Italian alphabet does not use all 26 letters that English does, e.g. they don't use J, K, W, X and Y so logically they skipped those, but they also skipped a few others like G, O, and sometimes E. So going from the patterns for A and B-prefix codes, we would expect:
CI = 2012 (last code I could find published)
CL = 2013
CM = 2014
CN = 2015
CP = 2016
Or maybe not. I have a Cimarron SAA with a CP proof code, but since I acquired it in June 2015, my assumed list can't be right. It would seem that CP is the proof code for 2015, and that the Italians skipped one of the letters L, M, or N in the "C" series.
If anyone has more definitive info, I would love to find a reference.